Egg Muffins with Spinach and Feta — Eat This Not That

Ingredients

• 2 tsp (10 mL) olive oil
• 1 small onion, chopped
• 3 cups (750 mL) baby spinach
• 6 large eggs
• 6 large egg whites
• 3⁄4 cup (175 mL) nonfat milk
• 1 ⁄2 tsp (2 mL) salt
• 1 ⁄4 tsp (1 mL) ground black pepper
• 1 ⁄2 cup (125 mL) crumbled feta cheese