Sprinkle beef with salt & pepper & rub into meat. Poke holes in meat with sharp fork to allow marinade to sink in. You can also use a tenderizer such as this one.

Chop onion and garlic.

Whisk together onion, garlic, red wine, ketchup, soy sauce, Worcestershire sauce, brown sugar, and thyme until well blended.

Place meat in gallon size freezer bag, then pour marinade over meat. Squeeze air from bag & seal. Let meat marinate at least 6 hours or overnight. If preparing as part of a freezer cooking day, be sure to label the bag first, then freeze after sealing.

Thaw meat (if frozen.) Turn on broiler with broiler pan inside. Preheat pan for 10 minutes. Place meat on broiler pan, then return pan to oven on top rack, about 4" from heat. Broil for approximately 5 minutes per side (6 minutes if you prefer your meat more well done), watching closely.

(Optional) Pour leftover marinade in a small saucepan and bring to a boil.

Let cooked meat rest for 8 minutes, then cut into thin slices with a sharp knife. Drizzle marinade over top of meat, if desired.