Chop the washed spinach into small pieces. Melt the butter and roast the dressed onion till it turns to pink. Add ground beef and cook for 10 minutes until it boils out. Add salt and black pepper and keep mixing. Put the spinach into pan and cook 5 more minutes. Let it cool. On the side; put the flour, add the salt in a big bowl and mix. Make a hole in the middle of the bowl and break the egg. Pour the warm water into the bowl slowly and knead it. To have more homogenous dough, take it onto kitchen counter and continiue kneading. Cover the dough with a kitchen towel and let it rest for 10 minutes. After, cut the dough into 6 even pieces. Roll out the pieces with a roller pin upto 20-25 cm diameter. Fill them with spinach-ground beef filling. Fold them into D shape and press on the edges with a fork. Heat the sunflower oil in a pan and fry the dough bags until they become golden.
Bon Appetite!