- For the Filling
- 6 cups blueberries
- 2/3 cup granulated sugar
- 3 tablespoons cornstarch
- 1 tablespoon fresh lemon juice
- 1 teaspoon lemon zest
- 1/2 teaspoon ground cinnamon Pinch of salt
- For the Topping
- 1 cup old-fashioned rolled oats
- 3/4 cup all-purpose flour
- 1/2 cup packed brown sugar
- 1/2 teaspoon ground cinnamon
- 1/4 teaspoon salt
- 1/2 cup unsalted butter, cold and cubed
- 1/3 cup chopped pecans or walnuts (optional, but I always add them)