Heat oven to 375 degrees. Bring a large pot of water to a boil. Spray a 9x13 baking dish, set aside.
When water boils, cook lasagna noodles per package directions to al dente. Drain when done and lay flat on wax paper or parchment paper and cover with damp towel until ready to assemble.
While noodles cook, dice sausage and veggies.
Cook sausage in a hot, non-stick skillet until cooked through and crisp. Remove from skillet, drain and set aside.
Wipe out skillet and add the diced veggies and cook until tender, season to taste with salt, pepper, Italian seasoning and red chili flakes. When veggies are cooked add sausage and mix to combine.
Mix ricotta cheese, some shredded parmesan cheese and fresh basil and/or any other fresh herbs you'd like.
Set up assembly station: prepared baking dish, marinara or pasta sauce, noodles, cooked veg/sausage mix, ricotta mixture, shredded cheese.
Start by spreading a layer of sauce on the bottom of prepared baking dish, followed by a layer of lasagna noodles. Spread an even layer of ricotta cheese onto the noodles. Spread a layer of veg/sausage mixture over the ricotta layer, then sprinkle with shredded cheese. Then repeat - sauce, noodles, ricotta, veg/sausage mix, shredded cheese, ending with a layer of noodles topped with sauce and sprinkled with shredded cheese.
Cover dish with a piece of aluminum foil sprayed with cooking oil. Bake for 25 minutes until bubbly. Remove foil and bake another 15 minutes until cheese has melted and sauce is bubbly.
Remove from oven when done and let sit for 5-10 minutes before cutting.Sprinkle with some extra shredded parmesan cheese and fresh herbs.