In a large bowl, combine stew meat, flour, cumin, onion powder and garlic powder. Stir to coat well.
Coat bottom of frying pan with oil. Sear the meat in small batches making sure that it is browned all over.
When meat is seared, place in slow cooker.
Pour excess oil out of the frying pan (if any is left). Add onion to the pan stirring constantly to work all the brown bits from the meat off of the pan. Once the onion is transparent, add a little of the water to the pan to deglaze. Pour onto meat in slow cooker.
Add remaining water, gravy mixes, rotel tomatoes and green chili's.
Allow to cook on high heat in the slow cooker for 6-8 hours.
Serve on flour tortillas.
I always make sure to have shredded cheese, guacamole, sour cream and green onion ready to serve with it.
For sides, I will make a pan of pinto beans and plain white rice. If you have leftovers, this is also really good served over the rice or egg noodles the next day.
If you like spicier food, you can add fresh jalapeno or use the spicier rotel tomatoes.