Preheat the oven to 450°F. Line a sheet pan with foil. Wash and dry the fresh produce. Cut the potatoes into 1/2-inch rounds. Roughly chop the cheese curds. Grate the white cheddar on the large side of a box grater. Place the potato rounds on the sheet pan; drizzle with olive oil if desired. Season with salt, pepper, and half the spice blend. Toss to coat; arrange in an even layer. Roast 20 to 24 minutes, or until lightly browned and tender when pierced with a fork. Leaving the oven on, remove from the oven. Evenly top with the chopped cheese curds and grated white cheddar. Return to the oven and roast 2 to 3 minutes, or until the cheese is melted. Remove from the oven.

Meanwhile, halve, peel, and thinly slice the onion(s). Roughly chop the peppers. Thoroughly wash your hands and cutting board immediately after handling. In a bowl, combine the ketchup, half the mayonnaise (you will have extra), and as much of the chopped peppers as you'd like, depending on how spicy you'd like the dish to be. Taste, then season with salt and pepper if desired.

Evenly sprinkle the patties with the remaining spice blend. In a medium nonstick pan (or large for 4 servings), heat a drizzle of olive oil on medium-high until hot. Add the seasoned patties. Cook 4 to 6 minutes per side, or until browned and heated through. Transfer to a plate and cover with foil to keep warm.

Heat the same pan on medium- high until hot (if the pan seems dry, add a drizzle of olive oil). Add the sliced onion(s); season with salt and pepper if desired. Cook, stirring occasionally, 7 to 9 minutes, or until lightly browned and softened. Add the vinegar (carefully, as the liquid may splatter) and worcestershire sauce. Cook, stirring frequently, 30 seconds to 1 minute, or until combined. Transfer to a bowl. Taste, then season with salt and pepper if desired. Rinse and wipe out the pan.

Working in batches if necessary, add the buns, cut side down, to the same pan (add a drizzle of olive oil if desired). Toast on medium-high 30 seconds to 1 minute, or until lightly browned. Transfer to a work surface. Assemble the burgers using the toasted buns, cooked patties, caramelized onion(s), and as much of the sauce as you'd like. Serve the burgers with the cheesy potatoes. Serve any remaining sauce on the side. Enjoy!