In a dry sauté pan lightly toast the cumin (toast until very fragrant) and remove from pan to cool.
Char the Roma tomatoes and jalapeños over direct high heat until evenly charred and allow to cool.
Remove stems and seeds from jalapeños.
Place all the ingredients in a blender and pulse (do not over blend). Sauce should be slightly chunky.
Serve with chips or your favorite fajitas.Makes 2 cups Source: