Jen told me about this marinade on the Williams-Sonoma website, and it's delish! My steak was amazing.
2/3 cup basalmic vinegar
1/3 cup olive oil
2 T soy sauce
4 1/2 t firmly packed brown sugar
3/4 t freshly ground pepper
1/2 cup finely chopped fresh rosemary (can use dried too, just use less!)
5 garlic cloves, chopped
In a food processor, combine the vinegar, olive oil, soy sauce, brown sugar, and pepper and pulse until blended. With the motor running, drop the rosemary & garlic through the feed tube and continue to process until fairly smooth.