**Ingredients:**
– 2 cups all-purpose flour
– 1/2 cup sugar
– 1 tablespoon baking powder
– 1/2 teaspoon salt
– 3/4 cup milk
– 1/2 cup vegetable oil
– 2 large eggs
– 1 teaspoon vanilla extract
– 1 cup of your choice of mix-ins (chocolate chips, blueberries, nuts, etc.)
**Instructions:**
1. **Preheat Oven**: Preheat your oven to 375°F (190°C). Line a 12-cup muffin tin with paper liners or grease with cooking spray.
2. **Mix Dry Ingredients**: In a large bowl, combine the flour, sugar, baking powder, and salt.
3. **Mix Wet Ingredients**: In a separate bowl, whisk together the milk, oil, eggs, and vanilla extract.
4. **Combine**: Pour the wet ingredients into the dry ingredients and stir gently until just combined. Do not overmix; the batter should be lumpy.
5. **Add Mix-ins**: Fold in your choice of mix-ins gently to ensure they are evenly distributed.
6. **Fill Muffin Cups**: Divide the batter evenly among the muffin cups, filling each about two-thirds full.
7. **Bake**: Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
8. **Cool**: Allow the muffins to cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.