Spinach and Feta Frittata | RICARDO

Ingredients

• 2 small red onions, thinly sliced
• 1 tbsp (15 ml) apple cider vinegar
• 1 tsp (5 ml) maple syrup
• 3 tbsp (45 ml) vegetable oil
• 1 container (11 oz/312 g) or 2 containers of 5 oz/142 g each baby spinach
• 2 garlic cloves, chopped
• 10 eggs
• 1 cup (120 g) feta cheese, crumbled