Look for buckwheat flour ground from whole groats (the hulled seeds of the buckwheat plant). If you can’t find it, you can finely grind some whole roasted buckwheat groats in a coffee grinder and either use a full cup of that flour for a hearty taste or mix it with pale buckwheat flour for a somewhat more subtle flavor. Don’t fret about the first pancake you make, which rarely turns out well. As the Russians say, “The first pancake’s a lump.” You’ll quickly get the hang of it. These blini can be topped with any of the classic accompaniments, but they are so good on their own that Goldstein often just adds melted butter and a sprinkling of tolokno (toasted oat flour).