This is an exceptional sauce for fish tacos. In Ensenada Mexico, the self-proclaimed home of the fish taco, they deep fry the fish in a batter. It’s tasty, but I lightly coat talapia with flour, salt, pepper and garlic powder and saute in olive oil.
In a small electric blender, chop four cloves of garlic, add two or three jalapeno peppers (without their seeds) and one head of cilantro (minus stems), blend with 1/2 cup walnuts, 1/4 cup olive oil, the juice of one lime and enough water to make a spreadable paste. Season to taste with salt and freshly ground black pepper.