• Before starting, preheat the broiler to high. 
• Wash and dry all produce.
• Remove any brown spots from potatoes and cut into 1/2-inch pieces.
• To a large pot, add potatoes, 2 tsp salt and enough water to cover by approx. 1 inch (use same for 4 servings). Cover and bring to a boil over high.
• Once boiling, reduce heat to medium. Simmer uncovered for 10-12 min, until fork-tender.

• Meanwhile, peel, then cut onion into 1/4-inch slices.
• Heat a large non-stick pan over medium.
• When hot, add 1/2 tbsp (1 tbsp) oil, then onions. Cook for 3-4 min, stirring often, until softened slightly.
• Add 1 tsp (2 tsp) sugar and season with salt. Cook for 3-4 min, stirring occasionally, until onions are dark golden.
• Remove the pan from heat.
• Transfer onions to a small bowl, then set aside. Carefully wipe the pan clean.

• Meanwhile, in a medium bowl, combine beef, half the panko (use all for 4 servings), half the Dijon, 1/4 tsp (1/2 tsp) salt and 1/4 tsp (1/2 tsp) pepper. (TIP: If you prefer more tender patties, add an egg to mixture!) 
• Form into two (four) 5-inch-wide patties.

• Cut bacon strips in half crosswise.
• Reheat the same pan (from step 2) over medium-high. When hot, add bacon. Cook for 5-7 min, flipping occasionally, until crispy.**
• Remove from heat. Using tongs, transfer bacon to a paper towel-lined plate. Set aside.
• Discard bacon fat from the pan. Carefully wipe the pan clean.
• Heat the same pan over medium-high heat.
• When hot, add patties to the dry pan. Pan-fry for 4-5 min per side, until cooked through.** (NOTE: Don't overcrowd the pan; cook patties in 2 batches if needed.)

• Meanwhile, finely chop pickles, reserving pickle juice.
• Roughly chop parsley.
• In another small bowl, stir together half the pickles, ketchup and 1 tbsp (2 tbsp) mayo. (NOTE: This is your tangy sauce.) 
• When potatoes are fork-tender, drain and return them to the pot, off heat.
• To the pot with potatoes, add parsley, reserved pickle juice, remaining pickles, remaining mayo and remaining Dijon. Season with pepper, then gently stir to coat.

• Halve buns. On an unlined baking sheet, arrange buns, cut-side up. Sprinkle cheese over bottom buns.
• Toast buns in the middle of the oven for 2-3 min, until cheese melts. (TIP: Keep an eye on them so they don't burn!)
• Spread tangy sauce on top buns.
• Stack patties, caramelized onions and bacon on cheesy bottom buns. Close with top buns.
• Divide burgers and potato salad between plates.

If you've opted to add bacon, cut strips in half crosswise. Reheat the same pan (from step 2) over medium. When hot, add bacon. Cook for 5-7 min, flipping occasionally, until crispy.** Remove from heat. Using tongs, transfer bacon to a paper towel-lined plate. Set aside. Discard bacon fat from the pan. Carefully wipe the pan clean. Use the same pan to cook burger patties. 

Stack burgers with bacon when you assemble them.