1/3 cup gf bread crumbs 2 small green zucchini, thinly sliced 1 small yellow summer squash, thinly sliced 2 cups gf marinara sauce 1 cup parmigiano-reggiano, grated Kosher salt
Preheat oven to 450°F.
Lightly butter a 1 quart gratin dish. Sprinkle half the bread crumbs evenly over bottom of dish. Place half the zucchini over bread crumbs. Season with kosher salt. Pour half the gf marinara sauce over the top. Sprinkle half the cheese over the sauce. Continue layers with the remaining bread crumbs, zucchini, salt, gf marinara sauce and cheese.
Bake until gratin is bubbling and crisp on top, about 20-25 minutes. Serve warm or at room temperature.