You did it wrong.
Try my recipe, in a Coffee Mug.
1. Add 1/4 of a cup of flour, after greasing mug with oil.
2. Add 1/4 of a cup of sugar.
3. Sift 2 tablespoons of Cocoa to the cup.
4. Mix dry ingredients in the mug.
5. Combine 1 large egg, 3 tablespoons of Milk, and oil in a seperate bowl.
6. Beat egg, milk, and oil together.
7. Mix the egg, milk, and oil (mixed), with the dry ingredients (mixed).
8. Add a chocolate chips and vanilla extract in with the batter. Mix.
9. Put in a Microwave Oven for 3 minutes on HIGH.
10. Wait for it to cool down.
11. ????
12. (B)eat it.
Koopa is not a Muffin-Making girl.