Place the beans in a bowl and cover them with tap water.
Leave the beans to soak at room temperature uncovered, for at least 12 hours, preferably 24 hours, changing the water at least once (or anytime you see that the water has turned brown). Discard any floating shells.
Drain the beans and spread them onto a baking sheet lined with paper towels so that they air dry completely, about 5 minutes. Place the beans in the food processor with the onion. With the machine running, add some black pepper, cayenne and paprika, and process until you reach a fine paste.
Pour the oils into a large heavy-bottomed pot or casserole and heat the oil to 180˚C (350˚F), as measured with a deep-fat thermometer. If you don’t have a thermometer, drip a bit of batter into the oil – when you hear a sizzling sound and see the batter turning golden brown, the oil is ready.
Using two oval-shaped teaspoons, make little quenelles by scooping a bit of batter and transferring it from one spoon to another, putting some pressure against the spoons as you create the shape of a quenelle. Drop them directly into the hot oil. Only add as many as will fit in the oil without touching each other. Turn occasionally with a long slotted spoon, making sure all sides are browned evenly, about 3 minutes.
Transfer the fritters onto a baking sheet lined with a double thickness of kitchen paper to absorb any extra oil. Continue working in batches until all the fritters are cooked. Keep the finished batches in a warm oven, until serving. Serve immediately with a side of vatapa. These can be re-heated in the oven at Gas 2, 150˚C, fan130°C for 5 to 10 minutes.
Recipe from Cook Brazilian, by Leticia Moreinos Schwartz, photography by Ben Frink, published by Kyle Cathie, £19·99. Click here to buy the book.
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