In saucepan over medium heat, stir mashed beans in oil till smooth. Add seasonings and stir. Taste to see if it of your liking and adjust seasoning, if needed.
Slice your cheese to the thickness you like and big enough to fit your nacho. Slice jalapeno, serrano and set aside.
Place the chips on a microwave-safe plate(s). Spread beans on...as much as YOU like. Place slice of cheese on top of beans and then as many slices of pepper YOU like.
Place in microwave for 1 to 1&1/2 minutes. If cheese is not melted cook 30 seconds at a time till they are. Serve alone or as an accompaniment with other appetizers or mexican dishes.
NOTE: You can make less and refrigerate or freeze the beans if you're making these for 1 or 2 people. Otherwise this will make enough for 4 or 5. Adjust how much cheese and peppers to slice according to how many you will be feeding. This is something that can be made in a snap!