Mix together all marinade ingredients in a glass container. Add in meat. Marinate for 2 hours before cooking. Don't marinate for longer than 2 hours or meat will become tough and mealy.
Toss peppers and onions with spices and olive oil until well-coated.
Preheat grill to 350°F. Place grill basket on grill while preheating.
Add seasoned vegetables to grill basket. Cook for 30-45 minutes or until vegetables are tender and slightly charred.
When vegetables have cooked for 15-20 minutes, cook steak.
Place steak on grill and cook for 6-8 minutes or until grill marks are seen. Flip and cook an additional 6-8 minutes or until internal temperature reaches 120°F for medium rare. Let rest for 10 minutes before slicing.
After steak has rested, slice into ¼" slices, against the grain.
Warm tortillas and queso (if desired).
Add veggies and steak slices to warm tortillas and drizzle with queso. Serve with lime wedges. Enjoy!
I used the flat part of an elk bottom round roast but any flat steak (1 inch thick or less) will work. The flat iron steak or sirloin cap work great as well.
I used a pellet smoker but if you are using a gas grill, you can grill at a higher temperature.
Queso is not a necessary ingredient but it adds an extra level of deliciousness to your fajitas. Try it and you won't be disappointed!
If you don't have a grill, you can cook the meat on a grill pan on the stove and the veggies can be roasted in the oven.