Or, if the word "perogy" means nothing to you, you could call it baked potato pizza.
You will need...
3 cups of mashed potatoes, ish
1 tsp salt to make the potatoes taste better
1 onion, diced and sauteed
Olive oil for sauteing the onion
Mix the sauteed onion into the potatoes and let them sit in the fridge overnight and get to know each other. The next day, get your crust ready and spread the potatoes over it; I made them about 1/2 inch thick. Then top the potatoes with...
2 cups shredded cheddar
8-10 bacon slices, fried crispy and cut up
Bake this for ~20 minutes at 425, or at your discretion, and eat it with sour cream. This is the most filling pizza I have ever encountered, so use discretion when you're eating it, too.