Rinse the blueberries and pick through them to get rid of bad ones and remove stems, if visible. Drain well.
Place blueberries in a 9-inch round, oven-safe pie dish. Then add the maple syrup, lemon juice, lemon zest, cornstarch, and cinnamon. Gently stir to incorporate. Set aside.
In a large bowl, add the oats, almond flour, brown sugar, salt, and pecans. Pour the melted butter on top and stir together with a spatula until everything is moistened throughout.
Gently pour the topping on top of the blueberries and gently pat down if it's getting too high.
Place pie dish on a large baking sheet for easier transfer to and from the oven.
Bake for 50 minutes, or until the filling is bubbly and the crust is browned.
Let sit for 10 minutes before serving with a giant scoop of your favorite ice cream on top!
Notes
I highly recommend using fresh blueberries for this recipe. If you choose to use frozen blueberries, you may need more cornstarch as there is extra liquid in the frozen blueberries.