My favorite way to serve these beef fajitas is with flour tortillas, sour cream, fresh lime, and some cheese on top. I love to use plain greek yogurt instead of sour cream sometimes too! This is a healthier, high-protein option that tastes the same. Some other toppings you could do include - shredded lettuce, guacamole, pico de gallo, refried beans, or hot sauce. You could also turn this recipe into a ground beef fajita bowl with some rice or even serve it over lettuce as a salad!