Place the ground turkey, minced onion, breadcrumbs, egg, Worcestershire sauce, optional ketchup or Dijon mustard, garlic powder, onion powder, kosher salt, and black pepper in a large bowl. Mix gently with your hands or a fork just until the ingredients are combined.

Divide the mixture into four equal portions of about 4 ounces each. Shape each portion into a patty about 3/4 inch thick, then press a shallow indentation into the center of each patty to help limit doming as it cooks.

Refrigerate the shaped patties for 15–30 minutes if your schedule allows. Chilling helps the soft turkey mixture hold together more easily in the skillet or on the grill.

Heat a lightly oiled skillet or grill over medium to medium-high heat. If using a skillet, add 1 tablespoon of olive oil and allow it to become hot before placing in the patties.

Cook the burgers for approximately 5–6 minutes per side, turning them once. Continue cooking until browned and the center reaches 165°F (74°C) on an instant-read thermometer.

Transfer the cooked patties to a plate and let them rest for 2–3 minutes. Serve on light buns or sandwich thins with lettuce, tomato, onion, pickles, mustard, or other preferred toppings.