4 medium potatoes, boiled 100 g (1/2 cup) feta 1 red onion, grated Garlic, minced 1 egg 45 ml (3 tbsp) milk 5 g (1 tsp) salt 2 g (1 tsp) black pepper 30 g (4 tbsp) cornstarch 2 sprigs parsley, chopped 4 green onions, chopped