I made this with elk sirloin because I happened to have some. Beef would be a great substitute, I would just recommend a leaner cut. This is a quick, healthy, well balanced meal that is easily scaleable and adaptable to substitute with what is on hand.
Mix together the first 7 ingredients. I add about a teaspoon of chopped cilantro and a pinch of salt and pepper. This will be divided in half to marinate the steaks and serve with the fajitas.
Preheat your barbeque. Optionally you can fry the steak.
Saute vegetables on high heat until lightly browned and slightly softened.
Grill steaks to preferred doneness and rest for 5 minutes. Slice into strips against the grain.
Serve sliced meat and vegetables on warmed tortillas with sour cream, cheese, remaining sauce, and cilantro.
I had mixed greens and added them to the wraps. It worked very nicely with the vinaigrette. It is a nice optional touch to add more nutrients and a little extra flavor and texture.