|I used red onion because that's what I had on hand.|
Mix the Rotel tomatoes with 1 T each of Cumin, Chili Powder, and Oregano. Add 3 cloves of chopped garlic and salt and pepper to taste.
Pour mixture over chicken.
Cook on low 6-8 hours.
If you aren't using frozen chicken you could probably be ready to eat in closer to 4 hours.