Prep the slow cooker: Lightly grease the insert or use a liner for easier cleanup.
Layer the base: Add the diced onion and minced garlic to the bottom. Pour in the enchilada sauce, diced tomatoes with green chiles, and chicken broth.
Add the spices: Stir in chili powder, cumin, smoked paprika, oregano, salt, and pepper until the sauce is well combined.
Nestle the chicken: Place chicken breasts or thighs into the sauce, turning to coat. They should be mostly submerged.
Cook low and slow: Cover and cook on Low for 5–6 hours or on High for 2.5–3.5 hours, until the chicken is fork-tender.
Add mix-ins (optional): During the last 30 minutes, stir in black beans and frozen corn.
This warms them through without getting mushy.
Shred the chicken: Transfer chicken to a cutting board and shred with two forks. Return the shredded chicken to the crockpot and stir to coat in the sauce.
Brighten it up: Stir in the lime juice. Taste and adjust salt, pepper, or chili powder as needed.
Assemble the bowls: Spoon rice into bowls.
Top with the saucy chicken mixture, then add cheese, avocado, sour cream, cilantro, jalapeños, and a squeeze of lime.
Serve: Add hot sauce if you like it spicy. The mixture should be saucy enough to soak into the rice while still holding its shape.