In a large bowl, combine the steak, onion, bell peppers, jalapeño, chili powder, hot sauce, and 3/4 teaspoon salt.
Divide evenly among 4 bags. Freeze until ready to cook, up to 3 months.
In a large skillet, over medium heat, heat the oil (use 1 teaspoon per serving).
Empty the frozen contents of the bags into the skillet (use 1 bag per serving). Cook, covered, stirring occasionally to break up ingredients, for 10 minutes.
Raise heat to medium-high and cook, uncovered, until the vegetables are tender and the steak is cooked through, 2 to 6 minutes.
Serve with the tortillas and the salsa and sour cream, if desired.