Wash beans and soak it in a pressure cooker for 1 hour, put them to cook in same water until tender, about 20 minute. In a skillet heat vegetal oil saute ground onion, garlic and pepper.
Add a cup of beans in the skillet and mash well. Pour into the casserole with remaining beans. Add salt, black pepper, oregano, cumin, bay leaf and sugar.
Boil 20 minutes over low heat, add vinegar and cook wine and let uncovered until a medium thickened.
Just before serving add olive oil.
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