If making shish kabobs, cut the steak and/or chicken into chunks. Otherwise, you can leave the meat in whole pieces. Mix all ingredients except the meat in a large measuring cup or small bowl.
If using both steak and chicken, keep them separate for marinating. Pour marinate in with the meat in a zip-sealed plastic bag and place in the refrigerator for at least 6 hours or overnight. Grilling is the preferred cooking method for this marinade. But you can also sear the meat on both sides on the stovetop and finish it in the oven.
If you are making meat and vegetable shish kabobs, you can also marinate the vegetables for an hour or two. Onions, peppers, whole mushrooms and grape tomatoes work well on skewers.