1. Use fresh or frozen blueberries but do not thaw frozen berries to reduce bleeding 2. toss berries in flour to help prevent sinking 3. avoid overmixing to keep the crumb tender 4. substitute plain yogurt plus a splash of milk for buttermilk 5. add 0.5 tsp almond extract for a bakery style flavor 6. store airtight up to 3 days or freeze slices up to 2 months