Sultry Sirloin Gratin (or Shapherd's Pie for them) - Restaurant Association of Nova Scotia

Ingredients

• 1 onion, chopped
• 1 lb (500 g) Lean Ground Beef Sirloin
• π tsp (1mL) dried thyme
• Pepper
• π cup (50 mL) Worcestershire Sauce
• 2 tbsp (30 mL) tomato paste
• 1 tbsp (15 mL) all-purpose flour
• 2 cups (500 mL) frozen mixed vegetables
• 1 cup (250 mL) low-sodium beef stock
• Buttermilk mashed potatoes (recipe follows)
• ∏ cup (125 mL) EACH shredded aged and mild Cheddar cheese