01 -
Preheat the oven to 400°F. Line a standard muffin tin with paper liners.
02 -
In a small stainless steel skillet set over medium heat, melt the butter. Swirl the pan occasionally and continue cooking until the butter becomes foamy and makes crackling noises. Once the crackling stops, swirl until the butter has a nutty aroma and amber-colored bits form at the bottom, about 2 to 3 minutes. Remove from heat and pour into a medium mixing bowl, ensuring all browned bits are included. Let cool.
03 -
In a small bowl, mix the granulated sugar, flour, and cinnamon. Add the melted butter and mix with a fork until the texture resembles wet sand.
04 -
In a large bowl, whisk together the flour, sugars, salt, and baking powder. In a separate medium bowl, whisk together the cooled browned butter, buttermilk, egg, and vanilla extract. Combine the wet ingredients with the dry ingredients using a rubber spatula, mixing until just combined. Gently fold in the blueberries. Do not overmix. The batter will be thick.
05 -
Divide the batter evenly among the muffin tin cups. Sprinkle the crumb topping over the batter using your fingertips. Bake for 20 to 22 minutes or until golden brown and a toothpick inserted into the center comes out clean.
06 -
Transfer the muffin tin to a wire rack to cool for 5 minutes. Remove the muffins from the tin and cool completely on the rack. Serve immediately or store.