Cuban Black Bean Soup

Drain the soaked black beans and transfer to a large heavy pot. Add half the diced onion, half the diced green pepper, and the bay leaf. Cover with cold water by 7 cm. Bring to a rolling boil, skimming any grey foam that rises in the first 10 minutes. Reduce to a steady simmer. Cook for 1.5–2 hours until the beans are completely, entirely soft — almost velvet-tender. The pot liquid will have turned a deep, inky purple-black. Do not add salt until the beans are fully tender (early salting toughens the skins). Reserve all the cooking liquid.

In a separate skillet, warm the olive oil over medium heat. Add the remaining onion and green pepper. Cook for 8–10 minutes, stirring occasionally, until the onion is soft and translucent with golden edges. Add the garlic and cook 1 more minute. Add the ground cumin and dried oregano, stir for 30 seconds until fragrant. This is the sofrito — the aromatic base that will give the soup its Cuban identity. It should smell deeply savory and warm, like the best Cuban kitchen imaginable.

Ladle about 3–4 large spoonfuls of cooked beans and their liquid into the sofrito pan. Using a potato masher or fork, mash these beans vigorously into the sofrito until you have a thick, dark paste. This is the classic Cuban thickening technique — the mashed bean paste will naturally thicken the whole soup. Pour the sofrito-bean paste back into the main bean pot. Add salt. Stir everything together thoroughly. Alternatively, use an immersion blender to blend about one-quarter of the soup directly in the pot, leaving the remaining three-quarters whole for texture. Bring back to a simmer.

Add the apple cider vinegar and sugar to the simmering soup. The vinegar is not optional — it cuts through the density and lifts the entire flavour profile. The sugar balances the acid. Stir and taste. Adjust salt, vinegar, and sugar in small increments until the soup has a rounded, slightly tangy depth — savory, earthy, with a bright acid finish. Simmer together 15 more minutes to marry the flavours. To serve, place a mound of white rice in each bowl and ladle the black bean soup around and over it. Finish with a generous spoonful of cold sour cream and offer hot sauce at the table.