Take a BIG mug like this one in the picture. I tried using one that holds two cups but it was too small.
Put the following in the mug:
1/4 cup sugar; 1/4 cup flour; 1 tsp baking powder
3 Tbsp Oil, 3 Tbsp Peanut Butter (Crunchy or Creamy), 3 Tbsp Milk, 1 egg
Whisk together in mug until smooth & mixed well.
Place in a microwave on high for 1 1/2 min. Check, should be bouncy like a cake, may have a little moisture on the sides. If not done microwave for 30 second intervals until done. Do not over cook or it gets rubbery
Finished product, very hot & yummy. Also very filling.