Preheat the oven to 350°F (175°C). Grease or line a muffin pan with paper liners. Set aside. In a medium bowl, mix flour, baking powder, soda, and salt.
In a separate bowl, whisk eggs and sugar until combined. Add melted butter and vanilla extract. Stir in milk and mix until smooth. Incorporate the dry ingredients gently.
Once the dry ingredients are incorporated, fold in berries if desired. Be careful not to overmix the batter. It should remain slightly lumpy. The berries can be fresh or frozen.
Spoon the batter evenly into the muffin pan, filling each cup about ¾ full. If you like a crunchy top, sprinkle sugar on top before baking.
Bake for 20-25 minutes, or until a toothpick inserted in the center comes out clean. The muffins should have a golden-brown top. Cool slightly before removing.
Serve warm with butter or your favorite jam. These muffins make for a quick, easy, and delicious breakfast option that can be enjoyed by the whole family.
