Holiday Sausage and Sweet Potato Breakfast Casserole

Ingredients (14)

• + 1 pound sweet potatoes, peeled and cut into 1/2-inch cubes add to pantry
• + 3 tablespoons extra-virgin olive oil, divided add to pantry
• + 2 teaspoons kosher salt, divided add to pantry
• + 1 teaspoon garlic powder add to pantry
• + 1 teaspoon freshly ground black pepper, divided add to pantry
• + ½ cup diced onion add to pantry
• + ½ cup diced red bell pepper add to pantry
• ✓ 4 cloves garlic, minced
• + 1 pound bulk regular pork sausage (such as Jimmy Dean®) add to pantry
• + 1 cup baby spinach leaves add to pantry
• + ½ cup shredded mozzarella cheese add to pantry
• + 1 tablespoon minced fresh rosemary add to pantry
• ✓ 10 large eggs
• + 2 tablespoons milk add to pantry