2 ½lbs.boneless, skinless chicken thighs(or sub with chicken breast)
1(15 ounce)can tomato sauce
1smallyellow onion,finely chopped
4clovesgarlic,minced (about 4 teaspoons)
1tablespoonfinely chopped canned chipotle peppers in adobo sauce
1teaspoonkosher salt,plus more to taste
1teaspoondried oregano
½teaspoondried thyme
1driedbay leaf
12tostada shells
Optional toppings: shredded Mexican blend cheese or queso fresco, fresh cilantro, pickled red onions, sour cream, lime wedges, diced avocado or guacamole, pico de gallo or salsa
Instructions
Combine the chicken, tomato sauce, onion, garlic, chipotles, salt, oregano, thyme, and bay leaf in a slow cooker. Cover and cook until the chicken reaches an internal temperature of 165°F, about 1-2 hours on HIGH or 3-4 hours on LOW. Shred the chicken with two forks.
Transfer the shredded chicken and sauce from the slow cooker to a large (12-14 inch) skillet. Cook over high heat, stirring occasionally, until most of the liquid evaporates, 10-12 minutes. Simmering the chicken and sauce in a skillet helps to concentrate the flavor, and prevents a watery sauce that could otherwise make the tostadas soggy. Taste and season with salt and ground black pepper, to taste.
Spoon a bit of the chicken onto the center of each tostada shell. Add the desired toppings and serve.
Notes
You do not need to add any extra liquid to the Crock Pot. The juices from the chicken, onion, and tomato sauce, as well as the condensation from the slow cooker, should be more than enough liquid by the end. You don’t want to water-down the sauce.