Trevor,
I found this in a book I have.
1 cup beef broth, 2 tblsp balsamic vinegar, 2 tblsp canola oil, 2 tblsp minced basil leaves, 1 tblsp dijon mustard, 2 cloves pressed garlic, 1 teaspoon sea salt, 1 teaspoon black pepper. Mix it together in a bowl. Put the tri - tip in a baking dish or...