Blueberry Crumb Loaf is a moist blueberry loaf cake with a thick, buttery cinnamon crumb topping that bakes up golden and a little crisp. It’s the kind of loaf I like when I want something simple and homey, but still nice enough to slice and set out.
The loaf itself is soft and tender thanks to sour cream in the batter, and the blueberries keep it feeling fresh. I also like an optional little lemon zest in there when I have it, because it makes the berries taste a bit brighter.
I usually make this for weekend breakfasts, casual brunch, or an easy dessert that doesn’t need frosting. It’s especially good with coffee, and it holds up well for slicing once it’s fully cooled.
Why You’ll Love This Recipe
That crumb topping: The buttery cinnamon crumbs are the best part for me. You get a little crunch on top with a soft loaf underneath.
Tender, moist loaf: Sour cream (or Greek yogurt) makes the crumb stay soft and not dry. It still slices neatly once it cools.
Blueberries in every slice: Two full cups of berries makes this feel like an actual blueberry loaf, not a plain cake with a few berries scattered in.
Reliable and straightforward: No mixer tricks or complicated steps. It’s the kind of recipe you can make on a normal day and trust it to work.
Easy to finish: You can leave it plain, or add the quick glaze if you want it a little sweeter and more “coffee cake” style.
Ingredients You’ll Need
Crumb Topping
- All-purpose flour: I use regular flour here. It’s what gives the crumb topping its structure so it holds in big, moist pieces instead of melting into the loaf.
- Light brown sugar: Brown sugar gives the topping that deeper sweetness and a slightly caramel-like taste. Dark brown sugar works too if that’s what you have.
- Ground cinnamon: This is the main flavor in the crumb topping, so use one you like. Fresh cinnamon (not ancient) really does make a difference here.
- Salt: Don’t skip it. It keeps the topping from tasting flat and too sweet.
- Unsalted butter: Melted butter is what pulls the crumbs together. If you only have salted butter, just keep the added salt on the lower side.
Loaf Batter
- All-purpose flour: Regular flour is right for this loaf. I don’t recommend swapping in cake flour here because the crumb can get a little too delicate with all the blueberries.
- Baking powder: This gives the lift. Make sure it’s not expired, because a loaf like this really depends on it.
- Salt: Just enough to bring out the vanilla and butter flavor.
- Unsalted butter: Softened butter creams best with the sugar, which helps the loaf bake up lighter. If your butter is too cold, it won’t mix in smoothly.
- Granulated sugar: This sweetens the loaf and keeps the crumb tender. I stick with white sugar here since the topping already has brown sugar.
- Eggs: Room temperature eggs mix in more evenly, so the batter stays smooth. If you forget, you can warm them in a bowl of lukewarm water for a few minutes.
- Vanilla extract: Simple, classic, and it makes the loaf taste like an actual cake instead of just “sweet bread.”
- Milk: Any regular milk works here. I usually use whole milk, but 2% is fine too.
- Sour cream: This is what makes the loaf moist and soft. Full-fat Greek yogurt is an easy swap and works basically the same.
- Blueberries: Fresh blueberries are great, but frozen are totally fine too (use them straight from the freezer). The main thing is being gentle when you fold them in.
- Flour (for tossing berries): A light toss helps keep the blueberries from sinking too much. It’s a small step, but it helps.
- Lemon zest (optional): I like it if I have a lemon around. It gives the loaf a cleaner, brighter blueberry flavor.
Optional Glaze
- Powdered sugar: This makes a quick glaze that sets up nicely once it sits for a bit. Sift it if yours is lumpy.
- Milk: Add just enough to get a drizzle consistency. Start small, because it’s easy to thin it out too much.
- Vanilla extract: A little vanilla keeps the glaze from tasting like plain sugar.
Recipe Instructions
- Preheat the oven: Heat the oven to 350°F and set a rack in the center. Grease a 9×5-inch loaf pan and line it with parchment paper, leaving some overhang so you can lift the loaf out later.
- Make the crumb topping: Whisk the flour, brown sugar, cinnamon, and salt until combined. Stir in the melted butter until you get large, moist crumbs, then chill the bowl while you make the batter.
- Mix the dry ingredients: In a medium bowl, whisk the flour, baking powder, and salt together. Set aside.
- Cream the butter and sugar: In a large bowl, beat the softened butter and granulated sugar until light and fluffy.
- Add the eggs and vanilla: Beat in the eggs, then mix in the vanilla extract.
- Add the milk and sour cream: Mix in the milk and sour cream until the batter looks smooth and well combined.
- Add the dry ingredients: Fold in the flour mixture just until you don’t see dry streaks. Stop mixing as soon as it comes together.
- Add the blueberries: Toss the blueberries with 1 tablespoon of flour, then gently fold them into the batter. If you’re using lemon zest, fold it in now too.
- Fill the pan: Spread the batter evenly in the prepared loaf pan.
- Add the crumb topping: Sprinkle the chilled crumb topping over the surface and press it very lightly so it sticks.
- Bake: Bake for about 55 minutes, or until a toothpick in the center comes out clean or with a few moist crumbs. If you have a thermometer, the center should be around 200°F to 205°F.
- Cool: Let the loaf cool in the pan for 15 minutes, then lift it out using the parchment overhang. Cool completely on a rack before slicing.
- Glaze (optional): Whisk the powdered sugar, milk, and vanilla until pourable, then drizzle over the cooled loaf.
Some of my tips!
This is the part that really makes a difference. If you only read one section, make it this one because this is where I share the little trick that helps the recipe turn out so well.
Recipe Tips & Tricks
Keep the crumb topping cold. If your kitchen is warm, the topping can get greasy fast. Chilling it while you make the batter keeps the crumbs chunky and helps them stay on top.
Don’t overmix once the flour goes in. Mix just until the dry streaks are gone. Overmixing makes the loaf tougher and can knock some air out of the batter.
Toss the blueberries with flour. It won’t “fix” every berry from sinking, but it helps. It also keeps the batter from turning purple right away when you fold the berries in.
Use foil if the top browns early. The crumb topping can darken before the center is fully baked. If you see it getting too brown, tent the loaf loosely with foil for the last part of baking.
Check the center temperature if you can. A thermometer takes the guesswork out, especially since blueberry loaves can look done on top while the middle is still a bit underbaked.
Make some touches!
There are plenty of easy ways to serve this depending on the occasion. Keep it simple, or add a few small touches to make it feel a little more special.
Serving Suggestions
- Coffee or espresso: This loaf is really nice with coffee, especially if you skip the glaze. I like it best with black coffee or a latte.
- Greek yogurt: A scoop of plain or vanilla Greek yogurt on the side makes this feel more like breakfast. Add a few extra berries if you have them.
- Fresh berries: A small bowl of blueberries or mixed berries is simple and makes the slices look a little more put-together on a plate.
- Butter: If you’re serving it plain (no glaze), a thin smear of salted butter on a slice is really good. I usually do this if the loaf is for breakfast.
Save it for later
This section covers how to store leftovers and what parts of the recipe you can prepare ahead of time.
Storage and Make Ahead
Store the loaf airtight at room temperature for up to 2 days. I usually keep it on the counter if it’s going to be eaten quickly. Once it’s cut, press a piece of parchment or plastic wrap against the cut side to keep it from drying out.
If you want it to last longer, refrigerate it for up to 5 days. The fridge can dry cakes out a bit, so keep it well covered, and let slices sit at room temp for a few minutes before eating.
You can also freeze individual slices or freeze the whole loaf once it’s completely cool. Wrap tightly, then thaw in the fridge overnight or at room temperature until it’s soft again.
If you glazed the loaf, the glaze may look a little different after chilling or freezing. It still tastes fine, and you can always add a fresh drizzle if you want.
A few quick answers
This section covers a few extra details that may help before you head to the recipe card.
Recipe FAQs
Can I use frozen blueberries?
Yes. Use them straight from the freezer (don’t thaw), then fold them in gently. You may need to add 5 to 10 minutes to the bake time depending on your oven.
How do I keep the blueberries from sinking?
Tossing the berries with a little flour helps, and a thicker batter helps too. Some berries will still sink a bit with a loaf like this, but the flour step makes a noticeable difference.
How do I know when the loaf is done?
A toothpick in the center should come out clean or with a few moist crumbs. If you have an instant-read thermometer, I aim for about 200°F to 205°F in the middle.
Can I swap the sour cream?
Full-fat Greek yogurt works well and is the closest swap. I wouldn’t use low-fat yogurt if you can help it, because the loaf won’t be as tender.
Why did my crumb topping get too brown?
Ovens vary, and the topping can brown faster than the loaf bakes through. If you notice it getting dark, tent the top loosely with foil and keep baking until the center is done.
You might also like
Before you go, take a look at a few other recipes below the recipe card. They use similar ingredients in a different way and are worth saving too.
MORE DINNER RECIPES TO TRY
Blueberry Crumb Loaf
INGREDIENTS
Crumb Topping
- 1 2/3 cups all purpose flour
- 2/3 cup light brown sugar packed
- 1 tsp ground cinnamon
- 1/4 tsp salt
- 1/2 cup unsalted butter melted.
Loaf Batter
- 2 cups all purpose flour
- 2 tsp baking powder
- 1/2 tsp salt
- 1/2 cup unsalted butter softened
- 3/4 cup granulated sugar
- 2 large eggs room temperature
- 1 tsp vanilla extract
- 1/2 cup milk
- 1/2 cup sour cream
- 2 cups fresh blueberries
- 1 tbsp all purpose flour for tossing blueberries
- lemon zest optional.
Optional Glaze
- 1/2 cup powdered sugar
- 1 tbsp milk
- 1/2 tsp vanilla extract.
INSTRUCTIONS
Prepare
- preheat oven to 350 F and set rack to center
- grease a 9x5 inch loaf pan and line with parchment leaving overhang.
Crumb Topping
- whisk flour brown sugar cinnamon and salt until combined
- stir in melted butter until large moist crumbs form then chill while making batter.
Batter
- whisk flour baking powder and salt in a bowl
- cream butter and sugar until light and fluffy then beat in eggs and vanilla
- mix in milk and sour cream until smooth
- fold in dry ingredients just until no dry streaks remain.
Add Blueberries And Assemble
- toss blueberries with 1 tbsp flour then gently fold into batter
- spread batter evenly in pan and sprinkle crumb topping over the surface pressing lightly.
Bake And Cool
- bake until a toothpick in the center comes out clean or with a few moist crumbs and internal temperature is about 200 F to 205 F
- cool 15 minutes in pan then lift out and cool completely on a rack before slicing.
Optional Glaze
- whisk powdered sugar milk and vanilla until pourable then drizzle over cooled loaf.
