Step 1: Add the Chicken - Place the boneless skinless chicken breasts right into the bottom of your crockpot. I like to spread them out a bit so the seasoning and sauce can work their way around each piece. Nothing fancy here. This is one of those recipes where you do not need to brown anything first or dirty an extra pan, and that is part of the beauty of it.
Step 2: Season the Chicken - Sprinkle the taco seasoning packet evenly over the chicken. Try to get a little seasoning on each piece so the flavor does not end up in just one corner of the pot. Taco seasoning is doing a lot of helpful work here, bringing in chili flavor, garlic, onion, cumin, and salt without asking you to open half the spice cabinet.
Step 3: Add the Onion and Sauces - Add the diced onion over the seasoned chicken, then pour in the enchilada sauce and the can of Rotel diced tomatoes and green chiles. Give the crockpot a gentle little shake if you want the sauce to settle around the chicken, but you do not need to stir much yet. As everything cooks, the onion softens, the sauces mingle, and the chicken soaks up all that good flavor.
Step 4: Cook Until Tender - Cover the crockpot and cook until the chicken is tender enough to shred. For a quicker cook, use the high setting for 3 to 4 hours. For a slower day, use the low setting for 6 to 8 hours. I know some slow cookers run hotter than others, so check the chicken when you get close to the time range. You want it cooked through and easy to pull apart with two forks.
Step 5: Shred the Chicken - About 30 minutes before the cooking time is finished, carefully remove the chicken from the crockpot and place it on a cutting board or in a large bowl. Shred it with two forks, keeping the pieces bite sized and tender. This is usually the moment when someone in my house walks through the kitchen and asks if dinner is ready yet. Not quite, but close enough that everybody starts hovering.
Step 6: Stir in the Tortilla Strips - Return the shredded chicken to the crockpot, then add the corn tortilla strips. Stir everything together so the tortillas are coated in sauce and tucked through the chicken. The tortillas will soften as they cook, thickening the mixture and turning it into that cozy enchilada casserole texture. Do not worry if it looks a little loose at first. The strips will drink up some of that sauce.
Step 7: Add the Cheese and Finish Cooking - Sprinkle the Mexican blend cheese evenly over the top. Put the lid back on and let everything cook for about 30 more minutes, or until the cheese is melted and the tortillas are soft. Try not to stir the cheese in right away. Letting it melt on top gives you that lovely cheesy layer that makes everyone excited to dig in.
Step 8: Add Toppings and Serve - Spoon the Crockpot Enchiladas into bowls or onto plates, then pile on your favorite toppings. Lettuce, diced tomatoes, black olives, jalapeno, avocado, sour cream, salsa, cilantro, or a squeeze of lime are all good choices. I like a little crunch and freshness on top because it balances the warm, cheesy filling underneath.