Prep the Ingredients. Start by preheating your oven to 350°F and greasing a mini muffin tin or lining it with mini muffin liners.
Make the Batter. In a medium-sized bowl, whisk together the flour, baking powder, and a pinch of salt. In another bowl, combine the melted butter, sugar, egg, milk, and vanilla extract. Gradually fold the dry ingredients into the wet mixture, stirring just until combined. Be careful not to overmix, as this can lead to dense muffins.
Add Your Favorite Mix-ins. Now’s the fun part! Fold in your favorite add-ins like chocolate chips, fresh berries, or nuts. This step allows you to personalize the muffins based on your preference or the occasion.
Fill the Muffin Tin. Using a spoon or small scoop, fill the mini muffin tin, making sure each cavity is about 3/4 full. This gives the muffins enough room to rise while baking without overflowing.
Bake to Perfection. Place the muffin tin in the preheated oven and bake for about 12-15 minutes, or until a toothpick inserted in the center comes out clean. The tops should be slightly golden and spring back when touched.
Cool and Enjoy. Once baked, allow the muffins to cool in the tin for a few minutes before transferring them to a wire rack to cool completely. Enjoy them warm with a bit of butter, or store them for later snacking!