Hash Brown Frittata

Bahan-bahan (4 porsi)

• 1 tablespoon vegetable or canola oil
• 2 cups frozen hash brown potatoes
• ½ cup finely chopped zucchini
• ¼ cup finely chopped sweet onion
• 6 large eggs
• ¼ cup milk
• ½ cup chopped tomatoes
• salt and pepper
• 1 cup shredded cheddar cheese