Preheat the oven to 400*F. Line a baking sheet with parchment paper or foil (for easier clean up). Otherwise, rub with about 1 teaspoon of oil to keep the zucchini from sticking.
Slice the zucchini lengthwise into thin slices about 1/8 inch thick. Place the zucchini slices on the baking sheet in one layer. Sprinkle with 1/8 teaspoon salt.
Roast for 20 minutes until softened (some will be lightly browned but you do not want them to be completely browned).
Remove and pat dry with towels -- this step is really important to keep your lasagna from being watery.
Meanwhile, stir together ricotta, Italian seasoning, garlic powder, red pepper flakes, and remaining 1/4 teaspoon salt in a small bowl; set aside.
Grease an 8 inch square baking dish with the oil.
When ready to assemble, place half of the zucchini slices on the bottom of the 8 inch square baking dish. Spread half of the ricotta mixture over the zucchini. Top with half of the tomato sauce. Sprinkle with 1/4 cup cheese.
Repeat with remaining ingredients: zucchini then ricotta then tomato sauce then mozzarella.
Bake uncovered for 20 minutes. Turn the oven to broil and broil for 2-3 minutes until cheese is golden brown and bubbly. Let sit for a few minutes before serving. Enjoy!
*Cooking and patting dry the zucchini before layering into the lasagna will help the zucchini release as much of their natural moisture as possible.*Part skim ricotta is best because it is typically less watery than full fat. This will keep your lasagna from being too watery.*You can add 8 ounces cooked ground beef or turkey in the layers for a heartier casserole.
Recipe from Living Well Kitchen https://blog.memeinge.com/zucchini-lasagna/