Oh, blini! Yes, I've seen them featured in every other period drama on Netflix lately, usually being devoured by someone contemplating a geopolitical crisis. They're basically fancy, thin Russian pancakes, often made with buckwheat flour, which makes them sound way healthier than they probably are once you pile on the traditional toppings.
Speaking of toppings, prepare yourself for a culinary adventure, or a heart attack, depending on your perspective. The classic accompaniment is sour cream (smetana), smoked salmon, and caviar. Yes, caviar. Because nothing says "casual breakfast" like fish eggs that cost more than your rent, LOL. You're meant to dollop on the sour cream, then a sliver of salmon, and finally, a generous (or not-so-generous, if you're on a budget) spoon of black or red caviar. They're typically served warm and eaten by hand, sometimes rolled up like a mini taco, or folded.
If caviar isn't quite within your daily grocery budget, or you prefer your fish in fillet form, simpler versions exist. You can also have them with jam, honey, or condensed milk, which is a bit more forgiving on the wallet and the palate. But honestly, if you're going to try blini, you *have* to experience the full caviar treatment at least once. Otherwise, it's just a pancake, isn't it? TBH, it's a great excuse to feel like royalty for a moment. :)