Combine all marinade ingredients in a re-sealable bag. Pierce meat several times with a fork, and then place inside the re-sealable bag. Seal, and carefully shake to thoroughly coat meat. Allow to marinate for at least 2 hours — the longer the better.
Pour liquid out of bag into a small bowl. Add catsup, steak sauce, and Worcestershire sauce; whisk to combine. Heat mixture in a small saucepan; bring to a boil, and then reduce to low heat.
Meanwhile, grill or broil the meat until done. Slice into thin strips, and serve sauce on the side along with mashed cauliflower (recipe below) and steamed green beans.
Steam cauliflower in a steamer basket over boiling water until tender.
Combine cauliflower with remaining ingredients in a large bowl or a food processor. Mash mixture in the food processor or by hand with a mixer, immersion blender, or potato masher.