I have to correct this recipe..... The filling is wrong and for a traditional Latvian Piragi you use pork.

The filling should be.

Bacon off cuts. Mixture of smoked and unsmoked. The more smoked bacon the saltier the finished piragi. The bacon has to be cut into very small pieces not minced! Use both clean bacon and the bacon fat as this is used to help cook the bacon. I usually make about 3 or 3 Lbs of bacon at a time.This can take a while but minced bacon is not very good in the finished item.
If you do 4Lbs of bacon use one large onion if you make less then use one small onion.

Mix both together and add a small amount of ground black pepper. leave for at least one hour for the flavour of the pepper and onion to infuse into the bacon.One option I have not added as it just seems to spoil it for me is a few caraway seeds.

place all the bacon into a large pan and cook until all the water has evaporated from the bacon and it is all cooked but not browned.

Use the bread recipe supplied and add a tea spoon of the cooked mixture into the dough and make into the traditional Piragi shape.

Once cooked wipe the surface of the finished piragi with butter and leave to cool.

It may not be very specific but the bacon has to be made to be slightly smoked but not to the point of being over powering.