• Adjust rack to top position and preheat oven to 425 degrees. Wash and dry all produce. • Cut potatoes into 1/2-inch-thick wedges. Halve, peel, and finely dice onion. Halve buns. Thinly slice tomato into rounds.

• Toss potatoes on a baking sheet with a drizzle of oil, 3/4 tsp garlic powder (11/2 tsp for 4 servings), salt, and pepper. (You’ll use the rest of the garlic powder in the next step.) • Roast on top rack until browned and crisp, 20-25 minutes.

• Meanwhile, in a small bowl, combine 1 TBSP onion (2 TBSP for 4 servings), vinegar, 1 tsp sugar (2 tsp for 4), and a pinch of salt. • In a separate small bowl, combine ketchup, sour cream, mustard, 1 tsp sugar (2 tsp for 4), and remaining garlic powder.

• Heat a drizzle of oil in a large pan over medium-high heat. Add remaining onion and cook, stirring occasionally, until browned and softened, 5-7 minutes. Season with salt and pepper. • Transfer to a plate.

• While onion cooks, form beef* into two patties (four patties for 4 servings), each slightly wider than a burger bun. Season generously with salt and pepper. • Once onion is done, heat a drizzle of oil in same pan over medium-high heat. Add patties and cook to desired doneness, 3-5 minutes per side. • In the last 1-2 minutes of cooking, top each patty with cheddar; cover pan until cheese melts.

• While cheese melts, toast buns until golden brown. • Drain pickled onion, discarding liquid. Stir into bowl with sauce. • Fill toasted buns with patties, griddled onion, tomato, and sauce. Divide burgers between plates; serve with potatoes and any remaining sauce on the side for dipping.