Rinse the beans and remove any bad ones and any debris, place in a large bowl and cover with 2 inches of water. Add 2 tablespoons of salt and stir that in. Cover the bowl and let that sit for at least 6 hours.
After 6 hours, drain and rinse the beans. You can see how much the beans swelled.
Place the beans in your pressure cooker. Add 8 cups of water, 1 teaspoon of salt, and the 2 tablespoons of cooking oil, the oil keeps the beans from foaming so do not skip the oil.
Place the lid on the pot, add the weight (jiggler), and bring the heat up to high. When the jiggler starts moving and releasing pressure, start timing this for 8 minutes, and turn the heat down to low or medium low to maintain the jiggler moving and releasing pressure.
At 8 minutes, turn off the heat and move the pressure cooker to an unused burner and allow a natural release of pressure. When the pressure is released, open the lid, use beans as needed in other recipes.