Heat the butter in a pan. First, fry the onions until they start to turn brown. Then fry the meat vigorously (approx. 10 minutes) until it becomes crumbly.
Then deglaze with a little water, add the spices (more or less depending on your taste) and the peas and cook for another 5 minutes. The water should have evaporated enough that the dumplings can be reasonably filled.
Cut the puff pastry into square sheets and roll out a little if necessary. Place some of the filling in the middle and close it to form a triangle. Then bake the dumplings at 180 ° C until the dough has turned golden yellow.