Preheat your oven to 350 degrees F. Spray the cups of a mini muffin tin with non-stick cooking spray and then set it aside.
In a large mixing bowl, whisk together the pancake mix, milk, oil, eggs, sugar, and vanilla. (Be careful not to overmix.) Fold in 1 cup of mini chocolate chips.
Portion the batter into the prepared muffin tin filling each up 1/2 way full. Sprinkle a few more chocolate chips on too of each cup.
Bake for 12-14 minutes or until the edges and tops are browned. Remove from the oven and cool to the touch before removing the muffins from the pan. Repeat with the remaining batter.
Notes
Freshly baked muffins will last 1-2 days stored in an air-tight container on the counter or for up to 1 week in the fridge. Place a paper towel on the bottom of the container. This helps with absorption and keeps the muffins from getting soggy.
Once cooled, these muffins may be frozen for up to 3 months in an airtight freezer bag.
To make regular-size muffins: Line a regular muffin tin with paper liners or with non-stick spray. Fill each muffin cup about 2/3rds full. Bake for 22-25 minutes or until the tops are brown and a toothpick inserted in the middle of the muffin comes out clean. You should get around 16 muffins.