Beefed Up Kebobs

1/3 c red wine vinegar1/4 c ketchup2 tbsp olive oil2 tbsp soy sauce1 tbsp Worcestershire sauce1 tsp Dijon mustard1 tsp salt1/4 tsp freshly ground pepper2 cloves garlic (I use the bottled minced garlic & use about a tbsp)1 lb sirloin cubesCombine all marinade ingredients and mix well. Place beef (and chicken) in a shallow non metallic container (I use a 9×13 glass dish) Marinate, covered, in the refrigerator for 2 hours or longer, turning occasionally. Remove meat from pan and put on skewers. I alternate chicken and beef but you could do them on separate skewers if you like. You could also add vegetables to the marinade and alternate them with the meat if you like as well. Grill or cook in the rotisserie till done.