This is another Whole30 favorite. It's super simple, but super delicious.
Chicken and Zucchini
3-4 tbs olive oil
1 lb chicken (breasts, thighs, or tenders) cut into bite sized pieces
1/2 onion, sliced
2 medium zucchini, cut into circles or half-moons
cayenne pepper (optional)
Heat 2 tbs olive oil in a large skillet over medium heat. Add onion, salt and pepper. When onion starts to soften, but not brown, add chicken. Sprinkle with salt and pepper. Cook, stirring occasionally, until chicken just starts to brown. Add zucchini, more oil, if neccessary, and season with salt, pepper, and cayenne, if using. Cook until chicken and zucchini are nicely browned and chicken is cooked through, about 5 minutes.