Rhubarb Upside-Down Coffee Cake is the kind of cake I like to keep around in spring, when rhubarb is everywhere and I want something a little more interesting than muffins. It’s a tender sour cream coffee cake baked over a brown sugar rhubarb layer, then flipped so the fruit ends up on top.
The flavor is what I want from rhubarb: bright and tangy, but still cozy with butter, vanilla, and a little cinnamon. The cake stays soft and moist from the sour cream, and the topping turns into that glossy, sticky fruit layer that makes upside-down cakes so satisfying.
I like this one for weekend breakfasts, casual desserts, and anything where you want a cake that looks special but feels simple. It’s especially good with coffee or tea, and I usually keep the serving style plain—maybe just a little powdered sugar.
Why You’ll Love This Recipe
Pretty on its own: The rhubarb layer bakes into a shiny topping, so you don’t need frosting or anything fancy to serve it.
Tender crumb: Sour cream gives the cake that soft, moist texture that holds up really well under the fruit.
Real rhubarb flavor: The brown sugar and butter round out the tartness, but you still get that classic rhubarb bite.
One-pan easy: It’s all built in one cake pan, and the “topping” happens while it bakes.
Easy to tweak: You can add pecans for crunch or swap in strawberries if your rhubarb is extra tart.
Ingredients You’ll Need
Rhubarb Topping
- Unsalted butter: This is what makes the topping taste rich and helps the brown sugar melt into a glossy layer.
- Brown sugar: I like packed brown sugar here for that deeper, caramel-ish flavor. Dark brown sugar works too.
- Rhubarb: Fresh is great, but frozen works if it’s thawed and well drained. Big watery pieces can make the topping a little loose.
- Vanilla extract: Just a little goes a long way in the topping and keeps the rhubarb from tasting too sharp.
- Ground cinnamon: This is subtle, but it makes the topping taste warmer and more “coffee cake” to me.
- Salt: A pinch helps the topping taste more balanced, especially with the brown sugar.
Coffee Cake Batter
- All-purpose flour: I use regular flour here. Spoon and level if you tend to pack flour into the measuring cup.
- Baking powder: This gives the cake most of its lift so it bakes up light instead of heavy.
- Baking soda: Works with the sour cream to keep the crumb tender and helps it brown nicely.
- Fine salt: Don’t skip it. It keeps the cake from tasting flat.
- Unsalted butter: Softened butter creams best with the sugar, so the cake stays fluffy instead of dense.
- Granulated sugar: I keep the batter fairly classic here so the rhubarb topping can be the main thing you taste.
- Eggs: Eggs give structure so the cake flips cleanly and slices without crumbling.
- Vanilla extract: Vanilla is a big part of the flavor in a simple coffee cake like this.
- Sour cream: This is what makes the cake moist and tender. Full-fat is my go-to.
- Milk: Use it only if your batter feels very thick. A splash helps it spread evenly over the fruit.
Optional
- Pecans: If you like crunch, chopped pecans are great scattered under the rhubarb. Walnuts work too.
- Powdered sugar: Totally optional, but a light dusting looks nice and keeps the serving simple.
Recipe Instructions
- Preheat the oven: Heat the oven to 350°F. Grease a 9-inch round cake pan, then line the bottom with parchment paper.
- Melt the butter: Melt the butter for the topping, then pour it into the prepared pan and tilt the pan so the bottom is evenly coated.
- Add the sugar: Sprinkle the brown sugar evenly over the melted butter.
- Season the rhubarb: Toss the sliced rhubarb with cinnamon and a pinch of salt, then scatter it evenly over the brown sugar. Drizzle the vanilla over the rhubarb.
- Mix the dry ingredients: Whisk the flour, baking powder, baking soda, and salt together in a medium bowl.
- Cream the butter and sugar: Beat the softened butter and granulated sugar until light and fluffy.
- Add the eggs and vanilla: Beat in the eggs one at a time, then mix in the vanilla.
- Add the sour cream: Mix in the sour cream until combined.
- Add the dry ingredients: Mix in the flour mixture just until you don’t see dry flour. If the batter feels very thick, add a little milk so it spreads more easily.
- Spread the batter: Spoon the batter over the rhubarb layer and spread it into an even layer, smoothing the top.
- Bake: Bake for 38 to 45 minutes, until the top is golden and a toothpick comes out clean.
- Cool and invert: Let the cake cool in the pan for 10 minutes. Run a knife around the edge, invert onto a plate while still warm, remove the parchment, then cool at least 15 minutes before slicing.
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
Use parchment on the bottom. Upside-down cakes are much less stressful when the bottom is lined. It also helps the rhubarb layer release cleanly.
Drain frozen rhubarb really well. Frozen rhubarb is fine, but it holds a lot of water. Thaw it, drain it, and pat it dry so the topping doesn’t turn soupy.
Don’t overmix once the flour goes in. Mix just until the last streaks of flour disappear. Overmixing makes the crumb tougher.
Add milk only if you need it. The batter should be thick, but spreadable. If it’s fighting you, a small splash of milk makes it much easier to smooth over the fruit.
Invert while it’s still warm. If you wait too long, the sugar layer can stick as it cools. Ten minutes is usually the sweet spot.
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
- Powdered sugar: Dust the top lightly right before serving. It keeps the look simple and doesn’t cover up the rhubarb.
- Whipped cream: A spoonful of lightly sweetened whipped cream is nice if you’re serving it as dessert. I like it best on slightly warm slices.
- Yogurt: For a breakfast-y plate, serve a slice with plain or vanilla Greek yogurt. It’s especially good if you used tart rhubarb.
- Ice cream: Vanilla ice cream is classic with upside-down cakes. Let the cake cool a bit first so the ice cream doesn’t melt instantly.
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 leftovers covered at room temperature for 1 day. After that, I move it to the fridge so the fruit topping stays in good shape.
Store leftovers covered in the fridge for up to 4 days. The cake firms up a little when cold, which is normal for a sour cream cake.
To serve, I usually rewarm slices for a few seconds in the microwave. You can also warm slices in a low oven if you’re heating several at once.
If you want to make this recipe ahead, you can bake it the day before and keep it covered in the fridge. Let it sit at room temp for a bit before serving, or warm individual slices.
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 rhubarb?
Yes. Thaw it first and drain it really well (and pat it dry) so the topping doesn’t get watery.
Can I swap in strawberries?
You can substitute about half the rhubarb with sliced strawberries. I like this when the rhubarb is very tart or you’re serving people who prefer a sweeter fruit topping.
How do I know when the cake is done?
The top should be golden, and a toothpick inserted into the cake (not straight down into the fruit layer) should come out clean. If it still looks pale and wet in the center, give it a few more minutes.
What if my topping sticks when I flip it?
Invert the cake while it’s still warm, and make sure you ran a knife around the edge first. If a few pieces of rhubarb stick to the pan, just lift them out and patch them back onto the top—it’s very forgiving.
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
Rhubarb Upside-Down Coffee Cake
INGREDIENTS
Rhubarb Topping
- 4 tbsp unsalted butter
- 3/4 cup packed brown sugar
- 3 cups rhubarb sliced 1/2 inch
- 1 tsp vanilla extract
- 1/2 tsp ground cinnamon
- pinch salt.
Coffee Cake Batter
- 2 cups all purpose flour
- 2 tsp baking powder
- 1/2 tsp baking soda
- 1/2 tsp fine salt
- 1/2 cup unsalted butter softened
- 3/4 cup granulated sugar
- 2 large eggs
- 2 tsp vanilla extract
- 1 cup sour cream
- 2 tbsp milk.
Optional
- 1/2 cup chopped pecans
- powdered sugar for serving.
INSTRUCTIONS
Prepare Pan And Topping
- Heat oven to 350 F and grease a 9 inch round cake pan then line the bottom with parchment
- melt 4 tbsp butter and pour into the pan then sprinkle evenly with brown sugar
- toss rhubarb with cinnamon and a pinch of salt then scatter evenly over the sugar layer and drizzle with 1 tsp vanilla.
Make Batter And Bake
- Whisk flour baking powder baking soda and salt
- beat softened butter and granulated sugar until light then beat in eggs one at a time and add 2 tsp vanilla
- mix in sour cream then mix in dry ingredients just until combined adding milk only if batter is very thick
- spread batter evenly over rhubarb and smooth the top then bake until golden and a toothpick comes out clean 38 to 45 minutes.
Cool And Invert
- Cool in pan 10 minutes then run a knife around the edge
- invert onto a plate while still warm and remove parchment
- cool at least 15 minutes before slicing and dust with powdered sugar if desired.
