Spinach Bacon Frittata

Bahan-bahan (4 porsi)

• 4 strips thick-cut bacon (chopped)
• 1/2 cup red onion (chopped)
• 9 eggs
• 3/4 teaspoon salt
• 1/2 teaspoon pepper
• 1/2 cup whole milk
• 4 cups spinach (fresh, packed)
• 1 clove garlic (minced)
• 1/3 cup green onion (1 tablespoon reserved)
• 1 cup gouda (shredded)