Heat cooking oil in a big pan/pot, oven-safe, over medium-high heat. Add onions and cook for 2 minutes. Add garlic and chili and cook for 2 to 3 minutes more.
Add all other veggies, except tomatoes, and cook for 5 minutes. Stir regularly.
Then add tomatoes, water (or stock), quinoa and all the herbs. Stir well, cover and simmer for 15-20 minutes, or until veggies are soft and quinoa cooked through. Stir occasionally.
When veggies are ready, remove from heat layer with cheese (or bread crumbs or (GF) panko) and grill cheese for 10 minutes in the oven. Or until nicely browned.