Spread diced chicken in a single layer on one side of your baking sheet.
Add broccoli florets to baking sheet in a single layer beside your chicken. Cut any large florets in half or thirds to ensure they cook evenly.
Spread sliced red onion in a single layer on baking sheet beside the broccoli.
Add cauliflower rice to baking sheet beside the onion. If you're ricing your own cauliflower just add florets to a high powered blender and blend until cauliflower has a rice-like consistency.
Drizzle balsamic vinegar over the chicken and broccoli.
Add minced garlic to your chicken.
Add salt, pepper, and olive oil to everything on the baking sheet.
Bake for 15 minutes.
Remove from the oven. Stir. Place back in the oven and bake for 5 additional minutes or until chicken is cooked to an internal temperature of 165F/74C.
Layer your cauliflower rice, red onions, broccoli, and chicken in bowls. Add a drizzle of balsamic vinegar if desired or more salt and pepper to taste. Top with basil and serve.