Preheat the oven to 375°F (190°C) and line a muffin tin with liners. In a large bowl, whisk together flour, sugar, brown sugar, baking powder, salt, and cinnamon.
In another bowl, whisk melted butter, eggs, milk, vanilla extract, sour cream, and lemon juice until well combined. Slowly add the wet ingredients to the dry ingredients, stirring gently.
Gently fold in the fresh blueberries, being careful not to overmix. Spoon the batter into the muffin liners, filling each about 3/4 full.
Bake for 18-20 minutes or until a toothpick inserted in the center comes out clean. Let the muffins cool for 5 minutes before transferring them to a wire rack. Enjoy warm or store for later.