Heat Taco Filling in a saucepan over low heat (or in the microwave). Warm tortillas in a dry skillet over medium heat (or directly over a gas burner), about 30 seconds per side.
To assemble, spoon taco filling onto tortillas, and top with lettuce, radishes, cheese, cilantro, and salsa. Fold to enclose.
Serve sour cream on the side. Garnish with diced jalapeno, if desired.