1
Adjust rack to middle position (top and middle positions for 8 servings) and preheat oven to 425 degrees.
Bring a large pot of salted water to a boil. (For 8, use two large pots or cook pasta in batches.)
Generously coat a 9-by-13-inch baking dish (two baking dishes for 8) with nonstick cooking spray and set aside.
Wash and dry produce.
Halve, peel, and finely dice onion. Zest and halve lemon.