Another delicious recipe from Cook's Illustrated!
36 oz frozen blueberries
1/2 cup sugar
1 tbsp cornstarch
pinch ground cinnamon
1 1/2 tsp grated lemon zest
1 tbsp lemon juice
1 cup flour
2 tbsp stone-ground cornmeal
1/4 cup sugar plus 2 tsp for sprinkling
2 tsp baking powder
1/4 tsp baking soda
1/4 tsp table salt
4 tbsp (1/2 stick) butter, melted
1/3 cup buttermilk
1/2 tsp vanilla extract
1/8 tsp cinnamon
1. Thaw frozen blueberries in a colander set over a bowl to catch juices. Transfer juices (roughly 1 cup) to a small saucepan and simmer over medium heat until syrupy and thick enough to coat the back of a spoon, about 10 minutes.
2. Adjust oven rack to lower-middle position and preheat oven to 375°.
3. For the filling: Stir the sugar, cornstarch, cinnamon and salt together in a large bowl. Add berries and syrup and mix gently with a rubber spatula until evenly coated. Add lemon zest and juice and mix to combine. Transfer berries to a 9 inch pie pan (or 8x8 pyrex dish). Place pan on rimmed baking sheet and bake until filling is hot and bubbling around the edges, about 30 minutes.
4. For the topping: Whisk flour, cornmeal, 1/4 cup sugar, baking powder, baking soda and salt in a large bowl to combine. Whisk together melted butter, buttermilk and vanilla in a small bowl. Mix 2 tsp of sugar and cinnamon in another small bowl and set aside. One minute before the berries come out of the oven, add wet ingredients to dry ingredients. Stir with a rubber spatula until just combined and no pockets of dry ingredients remain.
5. To combine: Remove berries from oven and increase temperature to 425°. Pinch off 8 equal sized pieces of dough and place on hot berry filling, spacing them at least 1/2-inch apart. Sprinkle each mound with cinnamon sugar mixture. Bake until filling is bubbling and biscuits are golden brown and cooked through, 20 to 22 minutes. Cool cobbler on wire rack for 20 minutes. Serve with vanilla ice cream or whipped cream.