Combine the turkey, Worcestershire sauce, gelatin, and onion powder in a bowl and mix well with your hands to incorporate everything evenly. Divide into quarters and shape each quarter into a burger patty. Set aside.

Combine all sauce ingredients in a small blender and process until completely smooth. Set aside.

Heat a large pan over high heat and when hot, add the oil. Sprinkle the outside of the burgers with the salt and then add to the hot pan. Cook on high heat for 5 minutes per side. You want a nice dark coloring to them. Then add a tablespoon or two of water to the pan and cover with a lid to steam the burgers until cooked through, another 5 minutes or so, until the internal temperature is 160ºF, or they are no longer pink when you cut them open. Transfer burgers to a plate to keep warm. Do not clean the pan.

Add the radish halves, cut side down. Add the chicken stock and cook on high heat, uncovered. Cook until the liquid is evaporated and the radishes are tender, about 10 minutes. Continue cooking, watching carefully, until golden brown on the cut surface of the radishes. Season with salt and pepper to taste then transfer to serving plates.

Add back the burgers to the pan and heat briefly to rewarm. Serve along with the radishes with the sauce drizzled over top and more parsley for garnish, if desired.