Cuban black beans usually require an overnight soak and hours of simmering. My dad loves this traditional process, but I’m determined to convert him to the Instant Pot method. It cuts the time down to under two hours from start to finish with no shortcuts on flavor! When you make these beans, don’t be afraid of having leftovers -- they taste even better the next day.
Combine the bell pepper, yellow onion and garlic in a food processor or mini food processor and pulse until finely chopped, working in batches if necessary (see Cook's Note).
Set a 6- to 8-quart Instant Pot® to saute and add the olive oil (see Cook's Note).
Transfer the green pepper mixture to the pot. Add the oregano, 1 tablespoon salt and season with black pepper. Cook, stirring occasionally, until the peppers are soft and the onions are translucent, about 5 minutes.
Add the beans, vinegar, vino seco, bay leaves, sugar and 5 cups water to the pot. Follow the manufacturer's guide for locking the lid and preparing to cook. Set to pressure cook on high for 30 minutes. (It will take about 10 minutes to come up to pressure.)
After the pressure-cook cycle is complete, follow the manufacturer's guide for natural release. After 20 minutes, being careful to release any remaining steam, unlock and remove the lid. Remove and discard the bay leaves. Scoop out 1 cup of the black beans into the food processor and pulse until almost smooth (see Cook's Note). If using a mini processor, be careful of any steam.
Return the beans to the pot and stir. Set the pot to saute and continue to simmer until thickened, about 10 minutes. Serve over white rice.