1 16-oz. box gluten-free lasagna noodles
3 Tbsp. olive oil, plus more to coat, divided
1 medium zucchini, thinly sliced lengthwise
1 yellow squash, thinly sliced lengthwise
Kosher salt and freshly ground black pepper to taste
2 tsp. dried herbs like basil, thyme or oregano, divided
1 small white onion, chopped
8 oz. button mushrooms, sliced
1 16-oz. jar pasta sauce
8 oz. cottage cheese, drained
8 oz. ricotta cheese
½ cup grated Parmesan cheese
1 tsp. garlic powder
5 oz. baby spinach leaves
8 oz. shredded sharp cheddar, divided
8 oz. shredded mozzarella cheese, divided
Preheat the oven to 350 degrees.
Bring a large pot of salted water to boil with 1 tablespoon olive oil. Cook the lasagna noodles under just tender enough to roll easily, about 5 minutes. Drain the noodles and lightly coat each with more olive oil to keep from sticking, then lay them flat on an olive oil-coated baking sheet until ready to use.
Prepare a charcoal or gas grill for indirect heat or place a grill pan over medium-high heat.
Toss the zucchini and yellow squash with olive oil to coat and season with 1 teaspoon herbs and salt and pepper to taste. Grill the zucchini and squash until tender and a bit charred, about 5 minutes, then flip and grill another 5 minutes. Remove and set aside.
Heat 2 tablespoons olive oil in a skillet over medium-high heat. Saute the onion and mushrooms with the remaining 1 teaspoon herbs until lightly brown, about 10 to 12 minutes. Remove from heat.
Roughly chop the grilled zucchini and yellow squash and toss with the mushrooms and onion. Set aside.
Spoon a thin layer of pasta sauce on bottom of 13-by-9-inch glass baking dish, then cover with the chopped vegetables.
In a medium bowl, stir together the cottage cheese, ricotta, Parmesan, egg and garlic powder until combined. Spread a thin layer of this mixture on top of each lasagna noodle, then sprinkle with a few tablespoons cheddar and mozzarella cheese and cover with a few spinach leaves.
Roll each noodle into a tight pinwheel and place spiral-side-down on top of the vegetables, packing together tightly so they stay closed. Cover the noodles with the remaining sauce and remaining cheddar and mozzarella cheese. Place the pan on a baking sheet to catch any drippings and bake 35 minutes, until the sauce and cheese are bubbly and slightly brown. Cover with foil and bake another 10 minutes. Let rest 15 minutes before serving.