How to Make It
In a bowl, mix the tomatoes with the onion, jalapeño, cilantro, lime juice and salt.
In an enameled medium cast-iron casserole, melt the cheese with the milk over low heat, stirring often, until smooth, 7 minutes.
Meanwhile, melt the butter in a medium skillet. Add the jalapeños and onion and cook over moderately high heat until softened, about 7 minutes. Stir in the cumin and salt.
Stir the jalapeño mixture into the melted cheese. Off the heat, stir in the pico de gallo. Serve hot with tortilla chips and lime wedges.