Place potatoes in a pot, add enough water to cover potatoes then bring to a boil over medium/high and continue cooking 25 minutes or until easily pierced with a fork. Drain and cool 5 minutes then mash potatoes until smooth.

Mash in ½ tsp salt, 2 Tbsp melted butter and 2 oz cream cheese. Mash in ¾ cup shredded mozzarella cheese. Partially cover and set aside while rolling out the dough.

In the bowl of a stand mixer (or large mixing bowl if mixing by hand), whisk together 1 cup warm water, ¼ cup milk, 2 Tbsp sour cream, 1 egg, 3 Tbsp oil, and 1 ½ tsp salt until blended.

Using the dough hook attachment (or wooden spoon if done by hand), add 2 cups flour and mix on speed 2 until incorporated. Add remaining flour ½ cup at a time, letting it incorporate before adding more. Add the last bit of flour, 1 Tbsp at a time, just until the dough no longer sticks to the sides of the bowl, or to your hands. Knead on speed 2 or by hand for 2-3 minutes until the dough is smooth and elastic. Cover with plastic wrap and let rest for 30 minutes.

Divide dough into 2 pieces. Cover the second piece and thinly roll the first piece out onto a floured surface to just under ⅛” thickness.

Use a 3” diameter round cookie cutter to cut circles from the dough, keeping them as close as possible (collect scraps and keep covered to re-use). Add ½ Tbsp of potatoes over each round (a mini scoop makes portioning easy).

To form pierogi, pull the 2 edges together and pinch tightly to seal. To ensure a tight seal, crimp the edges a second time with a pinch and twist motion. Cook or freeze pierogi for a future dinner (see freezing instructions in post).

Make the topping before boiling pierogi so it’s ready to drizzle over pierogi to prevent sticking. In a medium skillet, saute bacon. Once crisp, melt in 2 Tbsp butter and remove from heat.

Bring a pot of water to a rolling boil and add 1 Tbsp salt. Add fresh or frozen pierogi in batches. Cook for about 2 minutes or until the water has returned to a boil and the pierogi float to the top. Remove to a bowl with a strainer or slotted spoon drizzling buttery bacon between layers.