1.Preheat your oven to 400° F.
2.Combine the flour, baking powder, sugar and salt in a large bowl.
3.In a separate bowl, beat the eggs and then add the milk and vanilla.
4.Thoroughly grease and flour a muffin pan (or insert paper muffin liners).
5.Slowly pour the melted butter into the egg-vanilla-milk mixture, stirring briskly until all the butter is incorporated.
6.Add the liquid ingredients to the dry ones and stir for 10 to 15 seconds. The batter will still have some lumps in it, but that''s okay. If you overmix the batter, your muffins will turn out tough and rubbery.
7.Using a rubber spatula, gently fold the blueberries into the batter. Then carefully spoon the batter into the prepared muffin pan (you can use a small ladle or even an ice-cream scoop) and bake immediately.
8.Bake 18-20 minutes or until the muffins are slightly golden brown and a toothpick inserted into the center of a muffin comes out clean.
