This popular Ukrainian dish is also known as pyrohy, perogies or potato dumplings. Cheesy potato filling surrounded by a tender, almost non-existent, dough that melts in your mouth. This dough is so tender that I use vegetable oil if there is any left over varenyky. They are easier to pull apart after they have been refrigerated. Your could drizzle oil over the varenyky toss and then add the onion butter. Company's Coming.. Internation Buffet.