Preheat the oven to 375°F
Line a muffin tin with paper liners or grease the cups
In a large bowl, add pancake mix
Add eggs, milk, and melted butter or oil
Stir until just combined
Fold in optional mix-ins like blueberries, chocolate chips, or nuts
Fill muffin cups about 2/3 full
Bake for 15 to 20 minutes
Check for doneness with a toothpick
Let muffins cool in the pan for 5 minutes
Transfer muffins to a wire rack to cool completely