• Adjust rack to top position and preheat oven to 425 degrees. Bring a large pot of salted water to a boil. Line a baking sheet with foil. Wash and dry all produce. • Using the tip of a spoon, remove and discard black gills from undersides of portobello mushrooms; trim any large stems, if necessary. Trim and halve zucchini lengthwise; cut crosswise into ½-inch-thick half-moons. • 4 SERVINGS: Adjust racks to top and middle positions.

• Toss zucchini on one side of prepared baking sheet with a drizzle of olive oil, ½ tsp Italian Seasoning (be sure to measure), salt, and pepper. • Drizzle both sides of each portobello mushroom with olive oil; rub to evenly coat. Season all over with salt, pepper, and ½ tsp Italian Seasoning. Arrange mushrooms gill sides down on empty side of same sheet. Roast on top rack until tender, 14-16 minutes. • 4 SERVINGS: Use 1 tsp Italian Seasoning each for zucchini and mushrooms. Divide between 2 baking sheets; roast zucchini on top rack and mushrooms on middle rack.

• Once water is boiling, add spaghetti to pot. Cook until al dente, 9-11 minutes. Reserve ½ cup pasta cooking water, then drain.

• Meanwhile, melt 1 TBSP butter in a large pan over medium-high heat. Add panko. Cook, stirring, until golden brown, 3-5 minutes. Turn off heat; transfer to a small bowl. Wipe out pan. • Return same pan to medium heat; pour in marinara. Bring to a simmer; cook, stirring occasionally, until warmed through, 2-3 minutes. Turn off heat. Reserve ¼ cup marinara. • 4 SERVINGS: Use 2 TBSP butter for panko; reserve ½ cup marinara.

• Once portobello mushrooms are tender, remove baking sheet from oven and transfer zucchini to pan with sauce. Flip mushrooms on sheet. Heat broiler to high. • Stir spaghetti and 1 TBSP butter into sauce. • Spoon reserved marinara into mushrooms, then mound evenly with mozzarella. Broil on top rack until cheese is melted and lightly browned, 2-4 minutes. • TIP: Watch carefully to avoid burning.

• If needed, stir reserved pasta cooking water a splash at a time into pan with spaghetti over low heat until pasta is thoroughly coated in sauce. Taste and season with salt and pepper. • Divide spaghetti between plates and top with cheesy mushrooms. Sprinkle with toasted breadcrumbs and serve.