Ingredients
Scale
- 6 cups fresh or frozen blueberries
- 1/2 cup granulated sugar
- 2 1/2 tbsp cornstarch
- 1 tsp lemon zest
- 1 tbsp lemon juice
- 1 tsp vanilla extract
- Pinch of salt
- 1 cup old-fashioned rolled oats
- 3/4 cup all-purpose flour
- 2/3 cup packed brown sugar
- 1 tsp cinnamon
- 1/4 tsp fine salt
- 8 tbsp (1/2 cup) unsalted butter, melted
- 1/2 cup chopped nuts (optional)
- Butter for greasing pan
Instructions
- Preheat oven to 375°F (190°C) and lightly butter a 9×13-inch baking dish.
- Toss blueberries with sugar, cornstarch, lemon zest, lemon juice, vanilla, and pinch of salt; spread evenly in dish.
- In a bowl, combine oats, flour, brown sugar, cinnamon, and fine salt.
- Pour in melted butter, stir until clumps form; fold in nuts if using.
- Scatter topping over blueberries, leaving small gaps for steam to escape.
- Bake 35-45 minutes (add 5-10 min if using frozen berries) until topping is golden and berry juices bubble.
- Cool 15-20 minutes before serving; serve warm with ice cream, whipped cream, or yogurt.
Notes
- Ensure slow, thick bubbles appear around edges to check filling is set.
- Adjust sugar if berries are very tart.
- Keep clusters in topping for crunch; avoid covering pan.
- Store at room temp 1 day, refrigerate 3-4 days, or freeze up to 2 months; reheat at 350°F until hot and bubbly.
- Optional variations: add extra lemon, nuts, mixed berries; use gluten-free oats/flour or dairy-free butter for dietary needs.
- Prep Time: 10 minutes
- Cook Time: 40 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
- Diet: Vegetarian