Best Shepherd's Pie Bake

Ingredients

• For the Mashed Potatoes:
• 5 medium boiled russet potatoes
• 1/2 cup buttermilk
• 1/4 cup water from boiled potatoes
• 1 teaspoon kosher salt
• 1/2 teaspoon black pepper
• 2 tablespoons plus 1 teaspoon of butter
• 2 large eggs
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• For the Filling:
• 1 pound extra lean ground beef
• 1 pound extra lean ground pork
• 1 medium onion, finely chopped
• 1 medium carrot, finely chopped
• 1 celery stick, finely chopped
• 1 zucchini, finely chopped
• 2 large garlic cloves, finely chopped
• 1 cup frozen peas
• 1/2 teaspoon all spice
• 1/2 teaspoon Cayenne pepper
• 1/2 teaspoon freshly ground black pepper
• 1 teaspoon thyme leaves
• 2 tablespoons no salt seasoning
• 1/4 cup Worcestershire sauce
• 1/4 cup buttermilk
• 1/4 cup water