This is the easy version of Steak Fajitas. It's no Fajita Republic BUT not as much time & work either.
I used two separate pans. One for the veggies and one for the steak.
Cut up a lean sirloin steak into strips. Throw it in a pan & brown it. Once browned, add a HALF pkg of powdered fajita mix and a 1/4 cup of water. Cook it on high for a few minutes and then simmer to thicken.
In the other pan, throw in your chopped red onions, red & yellow bell peppers and I even threw in some leftover mushrooms. Lots of olive oil and the other half of the powdered fajita mix. Cook until soft. I threw in a few drops of Balsamic Vinegar just to add a little tang.
Then take your tortilla and build it to your liking with cheese, sour cream, maybe guacomole, whatever you like.