Let’s bring this lasagna to life! These steps are straightforward and infused with little tips I’ve learned through years of joyful kitchen experiments.

1. Preheat your oven to 375°F (190°C).
2. Cook the lasagna noodles according to package instructions. Drain and set aside.
3. In a large skillet, heat olive oil over medium heat. Add onion and garlic, sauté until fragrant.
4. Add the bell pepper, zucchini, and mushrooms. Cook until just tender, about 5-7 minutes.
5. Stir in the spinach and cook until wilted. Season with salt, pepper, and optional red pepper flakes. Remove from heat.
6. In a saucepan, melt butter over medium heat. Stir in flour and cook for 1-2 minutes to form a roux.
7. Gradually whisk in the milk, stirring constantly until the sauce thickens. Add nutmeg, salt, and pepper to taste. Set aside.
8. Spread a thin layer of the white sauce at the bottom of a 9×13 inch baking dish.
9. Layer 3 lasagna noodles, half of the veggie mixture, half of the ricotta, and a third of the mozzarella and Parmesan cheeses.
10. Repeat the layers, finishing with a final layer of noodles topped with remaining sauce and cheeses.
11. Cover with foil and bake for 25 minutes. Remove foil and bake for another 15 minutes until cheese is bubbly and golden.
12. Let it cool for a few minutes before serving to allow the flavors to meld together beautifully.

Pro tip: Use a mix of mozzarella and Parmesan for the ultimate cheesy top layer that’s crisp yet gooey!