Cook potatoes in a pot with water and salt until fully cooked. Drain water.
Cube the bacon into small pieces.
When the bacon is halfway cooked add onions and cook until fully cooked, stir in butter until it melts.
Mash potatoes. Add half of the cooked bacon and onions (with the grease), cheese, chopped dill, and sour cream. Mix until fully incorporated.
Set aside.
make pierogi-
Divide dough into two balls. Leave one out to use and keep the second one covered.
Generously flour working surface. Roll out the first dough to about 15-16 inches in diameter.
Take a drinking glass or cookie cutter with and make indentations in the dough. Push all the way through.
Remove the dough you will not be using and place in freezer bags or over with plastic, so it does not dry up.
Add potato filling to the shaped dough.
Fold the side of the dough together and pinch to seal in the filling.
cook pierogis-
To cook the pierogis, bring water to a boil (the amount will depend on how much perogies you will be adding). Season water with salt.
Once the water starts boiling add the perogies. Once they float to the top, cook another 3-4 minutes. Don’t overcook or else the filling will start to come out and the dough will fall apart.
Drain the water from the pierogi.
Add the sauteed bacon and onion over the pierogis and serve with sour cream.