Add noodles to boiling water and boil until pliable, but still a little firm, 8-10 minutes. Noodles should be slightly underdone.

Drain noodles in a colander and rinse under cold water. Lay flat on a plate and set aside.

While noodles cook, prepare ingredients.

Halve and peel onion. Slice halves into thin strips.

Stem, seed, and slice red bell pepper into 1/4" strips.

Trim zucchini ends, quarter lengthwise, and cut into 1/4" dice.

Set aside 1/4 the mozzarella. Combine remaining mozzarella with ricotta in a mixing bowl.

Place a medium oven-safe pan over medium-high heat and add 2 tsp. olive oil. You may also use a cast iron skillet.

Add onion and red bell pepper to hot pan. Stir occasionally until vegetables begin to soften, 2-3 minutes.

Add zucchini and cook until lightly charred, 2-3 minutes.

Remove from burner.

Set aside 1/2 cup marinara. Add remaining marinara, cooked vegetables, half the red pepper flakes, and 1/4 tsp. salt in another mixing bowl. Taste, and add remaining red pepper flakes if desired.

Reserve pan; no need to wipe clean.

Create three lasagna layers in pan used to cook vegetables: Start with vegetable-sauce mixture, dollop with ricotta-mozzarella mixture, and top with cooked pasta. You may have to cut pasta to fit. Repeat two more times, finishing with a pasta layer.

Pour reserved marinara sauce over top, covering lasagna.

Top with reserved mozzarella.

Coat a piece of foil with cooking spray and cover pan. Place pan in hot oven and bake 15-20 minutes.

Uncover and bake until golden brown, 10-15 minutes.

Remove from oven and rest at least 5 minutes. Lasagna may appear watery at first, but liquid will be absorbed as it rests.

Serve family-style. Bon appétit!