Step 1: Preheat and Prepare

1. Preheat your oven to 375°F (190°C). Line a muffin tin with paper liners or grease lightly with butter or oil.

Step 2: Mix Dry Ingredients

1. In a large mixing bowl, whisk together the flour, sugar, baking powder, and salt.

Step 3: Combine Wet Ingredients

1. In a separate bowl, whisk together the milk, melted butter (or oil), eggs, and vanilla extract (if using).

Step 4: Combine Wet and Dry Ingredients

1. Pour the wet ingredients into the dry ingredients and gently fold together until just combined. Do not overmix—a few lumps are okay!

2. Fold in your chosen add-ins (e.g., berries, chocolate chips, cheese, etc.).

Step 5: Bake

1. Divide the batter evenly among the muffin cups, filling each about ¾ full.

2. Bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.

3. Let the muffins cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.