1
Adjust rack to top position and preheat oven to 425 degrees. Wash and dry all produce.
Cut potatoes into ½-inch-thick wedges. Trim and thinly slice mushrooms. Halve, peel, and thinly slice onion; mince a few slices until you have 1 TBSP. Halve buns.
4 SERVINGS: Mince a few onion slices until you have 2 TBSP.