Fall Potluck Casserole with Turkey and Squash [VIDEO Recipe]

Ingredients

• 1 tablespoon butter
• 1/2 large sweet onion diced
• 2 teaspoons crushed or minced garlic
• 1 pound ground turkey
• 1 teaspoon kosher salt
• 3/4 teaspoon poultry seasoning
• freshly ground black pepper to taste
• 1 pound butternut squash diced (I usually buy it pre-cut.)
• 8 ounces frozen chopped spinach thawed and squeezed dry
• 8 ounces frozen hash brown potatoes
• 2 tablespoons all purpose flour (spelt or gluten-free flour are OK)
• 1 1/4 cups milk
• 1/2 cup shredded parmesan cheese divided