Heat the olive oil in a large non-stick frying pan over medium-high heat. Add the mushrooms and cook, stirring occasionally for 5 minutes.
Add chopped zucchini and cook, stirring occasionally, for 5 minutes.
Add riced cauliflower, chicken, garlic and chili powder and stir until combined. Cook, stirring occasionally, for 5 minutes, or until cauliflower rice is desired tenderness. Add salt and pepper to taste.