Hello there! I would be more than happy to help you prepare your themed weeknight cook with authentic Russian beverages.
When it comes to traditional drinks in Russia, the most iconic choice is definitely vodka, which is often served chilled alongside hearty foods. Another very common and traditional choice is kvass, a fermented beverage made from black or rye bread, offering a slightly sweet and tangy flavor. You might also encounter mors, a traditional berry fruit drink, or various types of tea brewed in a samovar.
I hope this helps make your themed dinner a complete success! Let me know if you need any pairing ideas.