Vegetarian lasagne

Ingredients:

3 red peppers, cut into large chunks
2 aubergines, cut into ½ cm thick slices
8 tbsp olive oil, plus extra for the dish
300g lasagne sheets
125g mozzarella
handful cherry tomatoes, halved
For the tomato sauce
1 tbsp olive oil
2 onions, finely chopped
2 garlic cloves, sliced
1 carrot, roughly chopped
2 tbsp tomato purée
200ml white wine
3 x 400g cans chopped tomatoes
1 bunch of basil, leaves picked
For the white sauce
85g butter
85g plain flour
750ml milk