Peel and rinse yuccas. Cut in 2 or 3 pieces depending the size. Cook yuccas in salted water until soft and tender when pierced with a fork. Drain and cool.
Cut yuccas in ½ x 2 inches (1.5 x5 cm).
Heat oil in a skillet and fry yuccas until golden. Season. Drain fat in paper towel.
Yucca sticks may be freezed until ready to use. Remove from freezer and place immediately in hot oil until golden and crispy.
Serve with Huancaína Sauce as an appetizer.
Place ají in a blender. Pour milk and blend.
Sauté onion with garlic in oil until cooked.
Add this mixture to blender together with the cheese.
While blending add oil until a creamy sauce is obtained.