SPRINGTIME WHITE LASAGNA - Lasagna recipe with fresh seasonal vegetables

With the arrival of spring, we find the first vegetables of the season, fresh and tender.
Why not make a light lasagna with them? Here is the recipe with an attention to simplicity and taste.
Ingredients:
500 g / 17,63 oz washed seasonal vegetables
(broad beans, peas,celery, carrot, onion, spinach)
Oil, salt and pepper
500 ml / 2 cups milk
45 g / 6 tbsp flour
100 g / 3.52 oz Parmesan cheese
150 g / 5.29 oz mozzarella cheese
6 lasagna sheets
First of all choose fresh vegetables that are in season, in this case spring vegetables, so with delicate flavors, so we are going to make a white lasagna.
In a pot, brown 2 tablespoons of oil and half a chopped onion.
Add a stalk of celery and a carrot cut into thin cubes, brown for another minute and then add all the other vegetables. In this case it is broad beans, peas and spinach, but you can also use zucchini, green beans or other vegetables.
Brown everything together for a few more minutes.
Add salt, pepper and a cup of water.
Lower the heat and simmer, covered, for 10 minutes or until all the water has evaporated.
In the meantime, put half a liter of milk in a bowl, add 45 g of flour or cornstarch, mix well, and when the vegetables are almost cooked but still al dente, add the milk, mixing slowly until the milk thickens.
At this point, remove from the heat.
Add 250 g of ricotta and melt it into the sauce to make it creamier.
Now, using some lasagna pasta, make 6 layers, starting at the bottom with some sauce, then a lasagna sheet, more sauce, Grana or Parmesan cheese, mozzarella, basil, and so on in layers.
The last layer is just sauce and grated cheese.
If you want to add other ingredients between the layers, such as some cooked ham, browned sausage, non-spring mushrooms, pumpkin seeds... do as you like.
Bake in a preheated oven at 180° C for about 30 minutes.
This recipe can be frozen immediately after preparation; defrost the day before baking.