Adjust rack to top position (top and middle positions for 4 servings) and preheat oven to 425 degrees. Lightly oil a baking sheet. Wash and dry all produce. • Dice potatoes into ½-inch pieces. Cut broccoli florets into bite-size pieces if necessary. Finely chop chives. • Place 1 TBSP butter (2 TBSP for 4 servings) in a medium microwave safe bowl; microwave until melted, 30 seconds. Stir in panko, half the Fry Seasoning, half the cheddar (you’ll use the rest of the seasoning and cheese later), salt, and pepper.
Pat chicken* dry with paper towels; season with remaining Fry Seasoning, salt, and pepper. Place on one side of prepared sheet (for 4 servings, spread out across entire sheet). • Evenly spread a thin layer of mayonnaise onto tops of chicken (you might not use all the mayo); mound with panko mixture, pressing to adhere (no need to coat the undersides).
Carefully toss broccoli on opposite side of sheet from chicken with a drizzle of olive oil, salt, and pepper. (For 4 servings, add broccoli to a second sheet and roast on middle rack.) • Roast on top rack until broccoli is browned and tender and chicken is cooked through, 15-20 minutes. TIP: For a deeply golden crust, broil chicken for the last 2-3 minutes.
While chicken and broccoli roast, place potatoes in a large pot with enough salted water to cover by 2 inches. Bring to a boil and cook until tender, 15-20 minutes. • Reserve ½ cup potato cooking liquid, then drain and return potatoes to pot. • Meanwhile, place bacon* in a large, dry pan over medium-high heat. Cook, turning occasionally, until crispy, 6-10 minutes. • Turn off heat; transfer to a paper-towel lined plate. Once bacon is cool enough to handle, roughly chop.
To pot with drained potatoes, add sour cream, remaining cheddar, and 1 TBSP butter (2 TBSP for 4 servings). Mash until smooth and creamy, adding splashes of reserved potato cooking liquid as needed. • Stir in half the bacon and half the chives. Season with salt and pepper.
Divide chicken, potatoes, and broccoli between plates. Top potatoes with remaining bacon and chives. Serve.