Mix all the fajita seasoning ingredients in a small bowl; set aside
To make tortilla bowls, preheat oven to 400F/200C. Dampen the flour tortillas with a few drops of water. Mold them to shape on the exterior of fluted tortilla shaper bowls. If you don't have the shapers, see post for another method. Bake for about 5 minutes, or until the tortillas begin to brown and hold their shape. Remove from oven and cool completely. FYI you can make a bunch of these for later use.
Fill the tortilla bowls with about 1 cup of salad greens.
Heat oil in a large skillet. Add the thinly sliced steak and brown. Add the onion and cook until onion just becomes transluscent. Add the peppers and fry just until they turn a bright color. Add the fajita seasoning and stir well to blend.
Place the meat mixture on top of the salad greens in the bowl. Serve immediately