Preheat the oven to 180 degrees Celsius/350 Fahrenheit top and bottom heat.
Chop the bell peppers, zucchini and carrots and slice the mushrooms.
Heat some oil in a large skillet. Sauté the onion and garlic. Then add the bell pepper, zucchini, carrots and mushrooms. Add the herbs and crumble the stock cube over it.
Add the diced tomatoes and simmer for 15 minutes. Taste the sauce and add salt and pepper to taste.
Cut the eggplant into 0.5-inch slices and brush lightly with olive oil. Season with salt and pepper and grill on both sides for 3 minutes.
Now, make the lasagna. Place half of the eggplant in the bottom of a baking dish. Top with a layer of mozzarella and Parmesan, a layer of vegetable sauce, and then the lasagna sheets. Repeat this process. Finish with the vegetable sauce and the remaining mozzarella and Parmesan cheese. Optionally, sprinkle a few pieces of fresh basil on top.
Bake in the oven for 30 minutes or until the lasagna is cooked through (test by piercing with a fork) and the cheese is melted and golden brown. Serve with a fresh salad on the side. Enjoy!