I love saltibarsciai, too, nothing better on a hot summer day. This was not quite enough buttermilk for me, I used closer to a quart, I would say. Also, I do not add the eggs to the bowl, but only to individual servings, and I chop mine up. (If you make more than you can use at a sitting, the eggs will go funky.) Also, the potatoes I serve on the side, not mixed in. Usually I just serve plain boiled potatoes, but mashed potatoes are good, too. If you ever have roasted fresh beets lying around, try it with those.
Mmmmm saltibarsciai... A personal summer favorite! My family's recipe is a little bit different, instead of the buttermilk we use a couple of dollops of sour cream and water (and/or ice if you want it to chill faster), add some finely sliced radishes, and about a tablespoon or so of lemon juice or vinear, to taste. We usually don't put potatoes, either, but there's so many variations of this traditional cold vegetable soup out there that it all ends up being a matter of preference! It should end up a nice pink/fushcia color. Everyone who isn't Lithuanian that I've made this for seems skeptical when they hear what this cold "borst" consists of, until they taste it and beg for the recipe. A very unique and worthwhile recipe to try out if you've never had anything like it!