Preheat your oven to 400 degrees.
Chop the squash, zucchini, and red onion.
Arrange with the mushrooms on a baking sheet.
Coat with olive oil spray and season with half of the salt, pepper, garlic powder, and Italian seasoning.
Roast for 20 minutes. You don’t want them to cook all the way through. You just want them to soften up a bit and get a little color!
While the vegetables are roasting, saute the spinach until slightly wilted and add the garlic at the end so it doesn’t burn.
If you are using regular lasagna noodles, boil those according to package directions to al dente. If you are using oven ready lasagna noodles, do skip this step.
In a mixing bowl, combine the ricotta cheese with the rest of the salt, pepper, garlic powder, and Italian seasoning.
Once everything is all set, you are ready to assemble the lasagna. In a 9x13 baking dish, layer a bit of tomato sauce, then lasagna noodles, half of the ricotta cheese, half of the spinach, and half of the roasted vegetables.
Repeat one more time and top with the last bit of lasagna noodles, sauce, and top with shredded mozzarella cheese.
Cover with aluminum foil and bake at 400 degrees for 40 minutes, then remove the aluminum foil and bake for another 20 minutes.