Spiralized Winter Veggie Gratin

Bahan-bahan (8 porsi)

• Olive oil spray
• 1 medium (7 ounce sweet potato, peeled and spiralized)
• 1 pound carrots (1.5″ in diameter, peeled and spiralized)
• 1 ½ pounds whole butternut squash (peeled and spiralized)
• 2 medium (7 ounces total parsnips, peeled and spiralized)
• 1 ½ tablespoon olive oil
• 4 teaspoons fresh chopped thyme
• 1 tablespoon fresh chopped oregano
• 3 tablespoons fresh chopped Italian parsley
• 1 ¼ teaspoon Kosher salt
• Freshly ground black pepper (to taste)
• ½ tablespoon butter
• 1/3 cup chopped shallots
• 3 teaspoon all-purpose flour (or gluten free flour for GF)
• 1 cup fat free milk
• 1 tablespoon grated parmesan cheese
• 2 1/2 ounces grated Gruyere cheese (divided)