Heat 1 tablespoon olive oil in a large oven-safe skillet over medium heat.
Add 1 pound extra-lean ground chicken or turkey and cook, breaking it into small pieces, until browned and cooked through, about 5 minutes.
Stir in 2 1/2 cups reduced-sodium chicken broth, 1 cup brown rice, 1 cup mashed sweet potato, 3/4 cup salsa, and a pinch of salt and pepper until combined.
Increase heat to high and bring the mixture to a boil; let boil for 2 minutes.
Reduce heat to low, cover the skillet, and simmer until the rice is tender and liquid is absorbed, about 1 hour.
Stir in 4 cups roughly chopped fresh spinach, cover, and cook until wilted, about 2 minutes.
Sprinkle 1/2 cup reduced-fat Mexican cheese blend over the top, cover, and cook until the cheese melts, about 1–2 minutes.
Garnish with cilantro and serve immediately.
