Pour the flour through a sifter and into the mixing bowl. Add a half a teaspoon of salt and the egg (egg is optional).
Pour the 3/4 cup boiling water slowly into the bowl, while stirring the mixture around with a whisk. Try to remove as many lumps in the batter as possible.
Cover the bowl for five minutes and wait. Wash some dishes or something if you have nothing better to do. After 5 minutes, add the quarter-cup of cold water, and let it sit for 15 more minutes; wash some more dishes.
Add the 1/2 teaspoon of vegetable oil and knead the dough for a few minutes.
With a rolling pin, roll the dough on a flat surface until it is uniformly about 3 mm thick.
Cut circles out of dough; using a large cup or small bowl is an excellent replacement for a circle-cutter.
Find a pierogi recipe and filling you enjoy and make some Polish dumplings!