Preheat the oven to 350 degrees F.

Combine all the chopped vegetables (carrots, broccoli, zucchini, squash) with 1/2 teaspoon salt and steam briefly, for 2-3 minutes, to soften them just a bit (they’ll finish cooking in the oven after the lasagna is assembled).

In a medium bowl, combine the ricotta, spinach and a bit more salt. Mix well.

Lightly grease a 9X13-inch pan. Spoon about 3/4 cup of the pasta/marinara sauce onto the bottom of the pan and spread around. It will be a thin layer. Cover with four no-boil lasagna noodles, overlapping slightly. Spoon on 1/3 of the lightly steamed vegetables and spread evenly. Spread 1/3 of the ricotta mixture over the vegetables then sprinkle with 1/3 of the mozzarella and 1/4 of the Parmesan cheese. Pour 1/3 of the remaining sauce over the cheese, lightly spreading it to the edges. Repeat the layers (noodles, vegetables, ricotta, mozzarella/parm, sauce) two more times, ending with the last of the sauce. Sprinkle the remaining Parmesan cheese over the top. This lasagna will be piled high – above the rim of your 9X13-inch pan, but it will settle as it bakes.

Cover the lasagna with a sheet of lightly greased foil and place the 9X13-inch pan on a large baking sheet lined with foil (this is important since the lasagna will bubble and spit over the edge a bit as it bakes).

Bake, covered, for 50 minutes. Uncover and bake 10 minutes longer. Let stand for 15 minutes before serving.