COMBINE olive oil, red wine vinegar and mustard in a resealable plastic bag with the steak and let marinate for 2 hours to overnight. When you're ready to cook the steak, remove it from the marinade, pat it dry with paper towels and bring to room temperature and sprinkle with salt and pepper.
PRE-HEAT the grill on high heat. It's hot enough when you test with your hand about 1 inch away from the grill and it's too hot to keep it there for more than a second.
BRUSH the vegetables with olive oil, sprinkle with salt and pepper, and place in a grill tray on the grill.
PLACE the steak on the grill for 4–6 minutes per side.
REMOVE vegetables and steak from the grill. Let the steak rest for 10 minutes. Slice it against the grain, on the diagonal, and serve with the vegetables. Drizzle DHC's new Red Plum & Roasted Onion Conserve across the steak, garnish with fried shallots and enjoy.