Preheat the oven to 375°F. Spray a 9-inch fluted tart pan or round cake pan with nonstick spray.

Whisk together the almond flour, all-purpose flour, baking powder, cinnamon, and salt in a medium bowl.

Using an electric mixer, in a medium bowl, beat the butter, brown sugar, and ¼ cup of the granulated sugar together on medium-high speed until the mixture is super light and fluffy, 3 to 4 minutes.

Scrape down the sides of the bowl and with the mixer on medium, add the eggs one at a time, beating until each one is incorporated, followed by the vanilla. Increase the speed to medium-high and beat until the mixture is pale and nearly doubled in volume, 4 to 5 minutes. Fold in the almond mixture until no dry spots remain. Gently add 1½ cups of the blueberries by hand, making sure you don’t totally smush them.

Transfer the batter to the prepared tart pan and, using a spatula or the back of a spoon, smooth the top. Sprinkle the remaining 3 tablespoons granulated sugar on top and bake until the cake is deeply golden brown and pulls away from the edges slightly, 30 to 35 minutes. It should start to crackle a bit on top (what you’re looking for).

Remove from the oven and let cool completely before slicing.