Ingredients

• 1/2 lb Mexican queso fresco or mild feta cheese, broken into small pieces
• 1/2 cup half-and-half
• 1 1/2 tablespoons bottled ajì amarillo purée (available at kitchenmarket.com)
• 1 garlic clove, peeled and smashed
• 1/4 teaspoon black pepper
• 2 lb fresh yuca (cassava) or 1 1/2 lb frozen peeled yuca (not thawed)
• About 6 cups vegetable oil
• 1/4 teaspoon salt
• Special equipment: a deep-fat thermometer
• Garnish: fresh lime wedges (preferably Key limes)

Instructions

1. Pulse together sauce ingredients in a food processor until smooth.
2. Fry yuca: If using fresh yuca, trim ends and cut crosswise into 3-inch pieces, then peel, removing waxy brown skin and pinkish layer underneath. Cover yuca (fresh or frozen) with cold salted water by 1 inch in a 4-quart pot. Bring to a boil, then reduce heat and simmer until yuca is tender when pierced with a wooden skewer, 15 to 20 minutes. Transfer with a slotted spoon to several layers of paper towels to drain, then cool 5 minutes. Cut yuca lengthwise into 1/8-inch-wide wedges, discarding thin woody core. (If there are pieces that have white parts to them, return them to barely simmering water and simmer until almost translucent.) Heat about 1 1/2 inches oil in a 4- to 5-quart heavy pot over moderate heat until it registers 360°F on thermometer. Fry yuca in 3 batches, turning occasionally, until golden, 3 to 5 minutes per batch. Transfer with a slotted spoon to paper towels to drain. (Return oil to 360°F between batches.) Sprinkle fries with salt and serve with cheese sauce.
3. If using fresh yuca, trim ends and cut crosswise into 3-inch pieces, then peel, removing waxy brown skin and pinkish layer underneath.
4. Cover yuca (fresh or frozen) with cold salted water by 1 inch in a 4-quart pot. Bring to a boil, then reduce heat and simmer until yuca is tender when pierced with a wooden skewer, 15 to 20 minutes. Transfer with a slotted spoon to several layers of paper towels to drain, then cool 5 minutes. Cut yuca lengthwise into 1/8-inch-wide wedges, discarding thin woody core. (If there are pieces that have white parts to them, return them to barely simmering water and simmer until almost translucent.)
5. Heat about 1 1/2 inches oil in a 4- to 5-quart heavy pot over moderate heat until it registers 360°F on thermometer.
6. Fry yuca in 3 batches, turning occasionally, until golden, 3 to 5 minutes per batch. Transfer with a slotted spoon to paper towels to drain. (Return oil to 360°F between batches.) Sprinkle fries with salt and serve with cheese sauce.