1 (2-pound) beef tenderloin, halved and cut into 1-inch slices or 6-inch wooden skewers that have been soaked in cold water for 30 minutes.
Heat grill to high. Skewer 2 pieces of the beef onto 2 skewers so that the meat lies flat. Brush the meat liberally on both sides with the Garlic-Mustard Glaze. Grill the meat for 2 to 3 minutes per side until golden brown and cooked to medium-rare doneness, brushing with the remaining glaze while grilling. Remove from grill and serve.
Whisk together all ingredients in a small bowl. Cover and let sit at room temperature for 30 minutes before using.