Saute capsicum and onion in olive oil over medium heat until soft (about 5 minutes).
Add garlic, chilli and tomatoes and saute for 2-3 minutes.
Slice chicken breasts in half horizontally to give thin fillets. Arrange evenly over the pan and push down to be partly covered by tomato sauce. Saute for 3 minutes.
Sprinkle parmesan over each breast fillet and place pan in oven. Cook until breasts are just tender (about 6-8 minutes).
Serve each fillet with greens and potatoes - mashed or sliced thinly and baked for healthy chips.