Vegetarian lasagna

ingredients :
2 cloves garlic, crushed
  1 sweet potato cut
  1 zucchini, sliced
  2 potatoes, sliced
  ¼ pumpkin, sliced
  ½ red pepper, chopped
  10 sliced ​​mushrooms
  1 finely chopped onion
  1 can (400 g) chopped tomatoes
  1 jar of tomato pasta sauce
  Fresh lasagna sheets,
  80g spinach coarsely chopped
  1 tablespoon olive oil

For the bechamel sauce:
  30g butter
  2 tablespoons cornstarch
  500 ml of milk
  100 g grated cheese
method:
Preheat oven to 180 degrees and oil a large bowl with a height of 7 cm oven slightly.
Heat the oil in a large frying pan and fry the garlic, mushrooms and onion until tender. Add Capsicum, tomatoes cut into pieces and pasta sauce. Bring to a boil, then reduce heat and simmer 30 minutes or until the sauce has thickened.
Meanwhile, melt the butter in a saucepan. Then stir in the cornflour. Once the ingredients mixed, remove from heat and pour the milk gradually to avoid lumps. Put the pan back on the heat and cook for a few minutes or until the sauce begins to thicken. Add half the cheese and mix.
Place potatoes and sweet potatoes in the dish, then cover with half of the vegetable sauce, then a layer of pasta. Cover with a layer of pumpkin and zucchini and remaining vegetable sauce, finishing with a layer of pasta.
Pour the cause cheese on top of the dish and sprinkle with the remaining grated cheese.
Bake 40 minutes.
Let stand 15 minutes before serving.
http://fr.russellhobbs.com/recipes/cuisines/lasagne-vegetarienne/