We waited at the tram stop for about 10 minutes, wondering why it was so late in coming, and also why there was no one else waiting for it. I noticed a paper pasted on top of the tram schedule, and while I couldn't read it all, I saw that dates were listed. Apparently the line was closed for a ten-day period.
This turned out to indeed be the case. When we walked over to the City Center Sofia Mall we saw tractors digging up the tram lines there. We got into a taxi instead and took it to 76 Pirotska Street. And that is where we finally found the Contessa.
The waitress handed us menus and we were about to ask if she had menus in English when we noticed something very strange. The menus were listed in Hebrew! As noted in my September posting, the restaurant is located right near Sofia's Jewish School, and apparently they get quite a few Jewish visitors.
We chose shnitzel and chips, and it was very good! The portions were so large that we took home enough for another meal.
Now that we know where the Contessa is, and how good the food is, hopefully we'll be going back!