Clean the vegetables and cut into small pieces. Sauté onions with oil and add garlic, season well and not too fearfully! Add the strained tomatoes, tomato paste and water, stir to a sauce. Season with a dash of balsamic vinegar. Add the cut vegetables and cook in a large saucepan for 10 minutes.
In a casserole dish, layer first the sauce and then the lasagne sheets. There must always be enough liquid over the lasagne sheets, otherwise they will not be cooked. If there is any sauce left over, it can be cooked further and eaten as a vegetable the next day. That depends on the size of the baking dish.
Finally, cut the tomatoes into slices and place over the last layer of sauce. Spread the freshly cut basil on top, cover everything with cheese.
Put it in the preheated oven at 200 ° C top / bottom heat for approx. 25 - 30 minutes.
Tip: If you turn on the grill for 5 minutes at the end, the cheese will turn nice and brown.