Whisk together flour, baking powder, cinnamon, salt, baking soda, and nutmeg in a bowl until well combined.
Whisk together white sugar, brown sugar, and melted butter in a second, larger bowl until well combined. Whisk in eggs, lemon juice, vanilla extract, and almond extract until thoroughly combined. Add in milk and sour cream and beat until mixture is smooth, and no lumps remain. Pour in dry ingredients and fold in a few times until just moistened; there should still be some clumps of dry flour. Sprinkle blueberries over the batter, and fold in until just incorporated. Batter will be lumpy, but should not have patches of dry flour remaining in it. Do not overmix.
Place batter in the refrigerator for 8 hours to overnight.
Preheat the oven to 400 degrees F (200 degrees C). Grease two 12-cup muffin tins and line with paper liners.
In a small bowl, stir together turbinado sugar and cinnamon.
Fill each muffin liner to the top with the batter. Sprinkle sugar and cinnamon mixture over the top of each muffin.
Bake in the preheated oven until muffins are golden and spring back lightly when touched, 20 to 25 minutes. Remove from the oven and cool in the pan for a few minutes before removing to a wire rack to cool completely.
Cook's Notes:
For smaller muffins, you can simply fill the muffin liners 3/4 of the way full, and bake a few minutes less. I get anywhere from 18 to 24 muffins out of this recipe, depending on how big I make them.
For a citrus variation, leave out the cinnamon in both the batter and the topping. Then add either 1 to 2 tablespoons lemon or orange zest.
Try yogurt in place of sour cream, or buttermilk in place of regular milk, if desired. Don't use nonfat products, as they will make the batter watery as it sits. I do not recommend using frozen, or really juicy berries in this recipe as they will make the batter watery. Fresh blackberries, raspberries, or cherries would make good substitutes for the blueberries.
