Better-Than-Takeout Burgers with Sweet Potato Fries
Toss sweet potatoes with oil and 1/8 tsp. each salt and pepper in the prepared pan. Bake, turning occasionally, until tender and brown, 20 to 25 minutes. Meanwhile, combine ground beef, mushrooms, and the remaining 1/8 tsp. each salt and pepper in a medium bowl. Shape the mixture into 4 patties, about 4 inches in diameter. Preheat grill to medium. Oil the grill rack. Toast buns on the grill. Combine mayonnaise and 1 tsp....