Mummy Boome's Traditional Shepherds Pie

INGREDIENTS

• Cheesy Mashed Potatoes, recipe follows
• 1/4 cup heavy cream
• 4 tablespoons butter
• 1 cup grated mature white Cheddar
• 1 tablespoon tomato paste
• 2 pounds lean ground beef or lamb
• 4 pounds Yukon gold potatoes, peeled, quartered
• 1 1/2 cups garden peas
• 2 stalks celery, diced
• Salt and freshly ground black pepper
• 2 cloves garlic, crushed
• 2 carrots, diced
• Mashed Potatoes
• 1 tablespoon olive oil
• 1/2 cup beef stock
• 1 tablespoon butter
• 2 tablespoons Worcestershire sauce
• 1 onion, diced