Spinach dumplings

500 g spinach 1-2 spring onions, finely chopped 1 small yellow onion, finely chopped 150 g feta cheese, crumbled 2 tbsp olive oil 1 egg 2-3 tbsp fresh dill, finely chopped 1 tsp cumin (optional) Salt Pepper 20 gyoza wrappers (dumpling wrappers)