This blueberry cobbler recipe is a delicious summer dessert! In the unlikely event that you have leftovers, cover them and store them at room temperature for up to 2 days.
Preheat the oven to 400°F and grease an 8x8-inch baking dish.
In a large bowl, whisk together the all-purpose flour, whole wheat flour, sugar, baking powder, lemon zest, and salt. Form a well in the center and add the coconut milk and grated butter. Use a spatula to fold and form the mixture into a cohesive ball of dough.
Place the dough on a lightly floured surface and use a lightly floured rolling pin to roll it out into a ½-inch-thick circle. Use a 2¼-inch round biscuit cutter to cut out 9 to 11 biscuits, rerolling the scraps and dusting the surface with more flour as necessary. Transfer the biscuits to a parchment-lined plate or baking sheet and refrigerate while you make the filling.
Make the filling: In a medium bowl, combine the blueberries, sugar, cornstarch, lemon juice, and vanilla and toss until the fruit is well coated. Transfer the mixture to the prepared baking dish and arrange the biscuits evenly on top. Brush the tops of the biscuits with melted butter and sprinkle with coarse sugar.
Bake for 25 to 35 minutes, or until the fruit is bubbling and the biscuits are golden brown. Allow to cool for 15 minutes before serving.