Blueberry Muffins

Combine your dry ingredients: flour, baking powder, and salt.

In a bowl, whisk together the egg and sugar until fluffy and pale, then add softened butter, lemon zest, and vanilla extract, and mix well.

Gently fold in the flour mixture and sour cream, alternating between them and starting and ending with flour.

Add the blueberries to your batter, tossing them in a bit of flour first to prevent sinking.

Grease your muffin cups with butter, fill them with batter, and sprinkle brown sugar on top.