Let me start off by saying that I typically do not soak my dry beans when cooking them in the Instant Pot. Why, you ask?
When I first started using an Instant Pot four years ago, I wanted to test out the theory that dry beans don't need soaking before cooking in a pressure cooker. I have tested this so many times, I saw no need to soak ahead of time, because my time savings put the theoretical scale in favor of not soaking. And it seemed less fussy to deal with.
When I needed to make bean dip for my daughter's graduation party, I decided to go ahead and pre-soak the pinto beans I was making, partly because they were going to be mashed up anyway. And also since I was making them for a crowd, I decided to soak them. It was also a good way to test out pre-soaking dry beans since I hadn't done it for awhile. I use the IP so much for beans, you could call it my Bean Pot!
Refried Beans (or Bean Dip)
Pick through and rinse:
1 pound of pinto beans (or other beans of choice: black, kidney, red, etc.)
Soak with an adequate amount of water as the beans will double in size. I checked on my beans now and then and added water as needed. A good 8-12 hour soak should be good. Drain and rinse the soaked beans. Add fresh water to the beans in the Instant Pot inner pot, making sure the beans are covered.
Then add the following to the beans and water:
1 Tablespoon oil (I used olive oil)
3/4 cup (more or less) chopped onion
2 tablespoon minced garlic (maybe 4-5 cloves)
1 teaspoon mild chili powder
1 teaspoon cumin
1/2 teaspoon each - basil, oregano, cayenne pepper (any of these, or all, are optional)
1 teaspoon salt
1 bay leaf (remove after cooking)
Cook everything together on pressure cook setting for 25 minutes* on the high setting. For easy work to mash later, I find that letting the beans come down naturally off of pressure is best. Remove bay leaf. When it was done, I just took a masher (like a potato masher) and mashed it right in the pot. Some beans can be left whole.
Add:
vegetable broth (as needed, if you need more liquid)
Beans will thicken as they cool and absorb more liquid, so having broth/stock handy is a great idea. Depending on how thin or thick you want the finished bean dish to be, you might be surprised at the amount of liquid they will absorb.
This is easily doubled in an 8 quart IP. It can even be tripled in a 10 quart IP, as I also have one and tested this myself. A 6 quart IP can easily accommodate the one pound recipe above.
An immersion blender can be used, but I found no need with my potato masher. I have this Cutco potato masher in my kitchen with an old style handle. Tip: After using the masher, immediately rinse off your masher or immersion blender. You'll thank me later.
*You'll want to pressure cook for 35-40 minutes if not soaking the dry beans before cooking. Also make sure to add at least 6 cups of water for every pound of beans if not pre-soaking.
Optional: You can add a bell pepper to the cooking pot as well. (And/or a whole dried chili - remove before mashing the beans - chipotle maybe?) These additions can really give nice flavor!
