To prepare a sopa de fideos recipe, first you need to gather your ingredients. First, you'll need the following ingredients: 1 cup (240 ml) water 1 pound (450 g) chile flakes 1 teaspoon salt 12 tsp cayenne pepper 1 tablespoon kosher salt 2 tablespoons paprika (optional) 1 chopped scallions, if desired 2 ice cubes (or more) Salt and pepper to taste. Add the ingredients to the crock pot and cook on medium heat, stirring occasionally, until the vegetables are tender, about 30 minutes. Remove from the heat and stir in the lime juice and cilantro. Serve with tortilla chips.