Quick Blueberry Crumb Bars with Oat Topping

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are developed and reviewed.

A speedy dessert with a tangy blueberry filling layered under a buttery oat crumb topping, ideal for potlucks and casual gatherings. This American-inspired recipe, ready in about 60 minutes, layers all-purpose flour, old-fashioned oats, brown sugar, packed into a dessert worth slowing down for — great for weekend baking, holiday tables, or any time you want a sweet payoff at the end of a meal. Each serving lands at about 280 calories and feeds 9, so it slots into a weekend bake or a special-occasion dessert tray. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 15 min Cook: 45 min Serves 9 American cuisine 280 cal/serving
Build a week of meals around this recipe → Shop this recipe on Instacart → Shop equipment ↓

Ingredients

The bakeware we’d bake this in → Best Bakeware Sets in 2026: Top Picks + Buying Guide

Affiliate disclosure: AislePrompt may earn a commission on qualifying purchases made through Amazon links, at no additional cost to you. See our policy →

Equipment for this recipe

Tools this recipe's steps call for, with a link to each on Amazon.

More Bakeware & baking tools → Shop all kitchen tools →

Instructions

  1. Step 1: Preheat oven to 350°F. In a large bowl, combine 1 1/2 cups all-purpose flour, 1 cup old-fashioned oats, 3/4 cup packed brown sugar, 1/2 tsp baking powder, and 1/4 tsp salt.
  2. Step 2: Cut 3/4 cup cold cubed unsalted butter into the flour mixture using a pastry cutter or fingers until the mixture resembles coarse crumbs.
  3. Step 3: Press about two-thirds of the crumb mixture evenly into a greased 9x9-inch baking pan to form the base.
  4. Step 4: In a separate bowl, toss 2 cups blueberries with 1/3 cup granulated sugar, 1 tbsp lemon juice, and 1 tbsp cornstarch until berries are evenly coated.
  5. Step 5: Spread the blueberry mixture evenly over the crust layer.
  6. Step 6: Sprinkle the remaining crumb mixture over the blueberries to cover completely.
  7. Step 7: Bake for 40-45 minutes until the topping is golden brown and the blueberry filling is bubbling around the edges. Cool completely before cutting into bars.

Related recipes