This is what I use instead of refried beans for tacos or burritos dinners. It makes enough for two people, as long as there are plenty of tortillas and cheese and other toppings.
Soak 1 C of pinto beans and put into a pressure cooker. Add a large onion, cut into 8 chunks. Add water — enough so that the beans are almost covered, but not quite.
Pressure cook for 12-15 minutes and then let the pressure come down naturally.
Open the pressure cooker and mash the beans with a potato masher. Salt to taste, then stir in a couple of tablespoons of olive oil before serving.