Mixed salad greens, to taste Avocado slices, for garnish

In a medium bowl, combine the salsa with the pepper, cumin, and chili powder.

Place the onion and peppers on the bottom of a 4-quart slow cooker.

Place the chicken breasts on top of the onions and peppers.

Cover the chicken with the salsa and tomatoes.

Cook on low for 8 hours.

Shred the chicken with a fork inside the slow cooker, and stir everything together to combine.

Serve over mixed salad greens garnished with avocado slices.