Heat the oven to 425° F (220° C).
Toss the zucchini, peppers and onions in oil with the Italian seasonings, red pepper flakes, and salt and pepper in a medium bowl until thoroughly coated.
Spread the seasoned vegetables on a baking sheet and roast until tender crisp, about 25 minutes.
While the vegetables are roasting, cook lasagna noodles in boiling water to al dente, about 6-8 minutes. Drain and set aside.
Remove the vegetables from the oven and transfer them to a bowl. Stir in ½ cup of marinara.
In a separate small bowl, combine the ricotta and 2 tablespoons of the Parmesan cheese together.
Spread 2-3 tablespoons of the tomato sauce on the bottom of a lightly greased small baking dish (5x5 or 4x6”). Line the bottom of the dish with the noodles so that the noodles hang over the sides.
Top the noodles with the vegetables and sauce mixture.
Spread the cheese mixture over the vegetables and top with half of the mozzarella cheese. Fold the noodles over the top.
Top with the remaining marinara, mozzarella, and place the lasagna on a baking sheet. Bake until the cheese has melted, about 25 minutes.
Remove from the oven and let the lasagna rest for 10 minutes. Garnish with chopped basil before serving.