This is a recipe I found at Cinnamon Spice and Everything Nice. I made it with chicken a few weeks ago and it was delicious so it is going into my recipe box as my go-to fajitas recipe.
Recipe courtesy of her site.
SLOW COOKER UPDATE MAY 2021
Slice the meat against the grain. Set the slow cooker to browning, coat the meat with corn starch and the spices, garlic, salt and pepper. Brown. Add a little beef broth. Set up HIGH for 4 hours. After 3 hours add the sliced green peppers and onions.