Steam butternut for 10 minutes or until tender. Shake container or rake with fork to fluff. Meanwhile soak lasagna sheets in warm water for 10 minutes.
Make cheese sauce as follows: melt the cheese spread over low heat, add flour and cook gently for 1 minute. Add milk and stir until sauce thickens. Add feta cheese and stir until thick. Season to taste with salt, pepper and grated nutmeg.
Cut baby marrows into 1/4" slices on the diagonal.
Layer as follows in a square pyrex dish: 2-3 tablespoons of cheese sauce spread over base of dish, 2 sheets of lasagna, 1/3 of cheese sauce, butternut, 1/2 pasta sauce, lasagna, 1/3 cheese sauce, baby marrows and cherry tomatoes, pasta sauce, lasagna, and last 1/3 of cheese sauce.
Mix grated cheese and breadcrumbs and sprinkle over cheese sauce.
Bake in a moderate oven, 350° F (175° C) for 35 minutes until golden and bubbly.
Serve with tossed green salad.
There are 466 calories in 1 serving of Vegetarian Lasagna.