Aubergine and courgette Parmesan bake

Name: Aubergine and courgette Parmesan bake
Cuisine: European, Italian, Mediterranean
Ingredients: 2 large aubergines (approx. 700g), cut into 1cm discs; 2 large courgettes, cut into 0.5cm strips; 1 tbsp olive oil; 1 onion, finely chopped; 1 red pepper, finely chopped; 2–3 cloves garlic, crushed; 1 heaped tsp dried oregano; 1 x 400g can chopped tomatoes; 50g Parmesan cheese, finely grated; 120g reduced-fat mozzarella, thinly sliced