Transfer the raw chicken thighs to the bottom of the slow cooker. Add in the remaining ingredients (enchilada sauce, salsa, green chilis, and chopped onion) and give everything a big stir.

Secure the lid on the crock pot and cook on high heat for 4 hours, or low heat for 7-9 hours.

Transfer the chicken thighs to a cutting board using tongs. Use two forks to shred the chicken to your desired consistency. Transfer the shredded chicken back to the crock pot with the sauce and keep it warm until you’re ready to use it.

Store any leftovers in an airtight container in the refrigerator for up to 1 week.

Prepare the toppings you’ve chosen. Chop the lettuce, heat up the black beans, grate the cheese, slice the avocado, etc.

Heat the avocado oil in a large skillet over medium-high heat and wait for a few minutes for the oil to become very hot. The oil should be around 340 and 350 degrees Fahrenheit. This ensures the tortillas become nice and crunchy and don’t get soggy. If you have a laser thermometer, you can point it at the skillet to check the oil temperature before frying.

Carefully place corn tortillas in the hot oil and fry for 2-3 minutes per side, or until both sides are golden brown and have reached your desired level of crisp. Note: I use a 12-inch nonstick skillet for this, and I can fit 3 to 4 tortillas at a time.

Transfer the crispy tortillas to a plate lined with a paper towel and repeat for as many tortillas as you’d like.

Load up the crispy pan-fried tortillas with your desired amount of shredded chicken and your choice of toppings, such as black beans, salsa, cheese, sliced avocado, and chopped lettuce.

Note: if you're using refried beans, apply a thin layer of refried beans to the homemade tostada shells first so that everything sticks better.

Serve and enjoy!