Mix onion powder, chives soy sauce, garlic and sugar and stir until the sugar dissolves into the mixture.

Pour mixture over meat in a suitable salable container and refrigerate/marinate for 48 hours.

Add meat and marinade to a baking tray and cook a for 45 minutes at 350°F.

Remove from oven.

Separate meat from sauce and slice

Fry medallions in an oiled pan, adding small amounts of sauce until edges of medallions are crisp. Remove from heat.

Serve with remainder of sauce.