Preparation Simmer beans, onion, garlic, salt, and water in a 3-quart saucepan, covered, until beans are tender, about 8 minutes. Stir in cilantro and parsley and let stand, uncovered, 5 minutes. Drain bean mixture in a sieve and transfer to a food processor. Add cumin, cayenne, 3 tablespoons lemon juice, 4 tablespoons oil, dill, and mint and purée until smooth. Transfer to a bowl and cool to room temperature, stirring occasionally. Season with salt and pepper and add lemon juice to taste. Mound dip in a serving bowl and drizzle with remaining tablespoon oil. Cooks' note:• Dip keeps, covered and chilled, 3 days.
Preparation Simmer beans, onion, garlic, salt, and water in a 3-quart saucepan, covered, until beans are tender, about 8 minutes. Stir in cilantro and parsley and let stand, uncovered, 5 minutes. Drain bean mixture in a sieve and transfer to a food processor. Add cumin, cayenne, 3 tablespoons lemon juice, 4 tablespoons oil, dill, and mint and purée until smooth. Transfer to a bowl and cool to room temperature, stirring occasionally. Season with salt and pepper and add lemon juice to taste. Mound dip in a serving bowl and drizzle with remaining tablespoon oil. Cooks' note:• Dip keeps, covered and chilled, 3 days.