We visited Freiburg last week and though it wasn't nearly as tasty as Strasbourg, we did have two great finds.
First... At the farmer's market, one tiny stand had a long line, apparently only one product, and was selling it at lightning speed. On principle, I like any booth that has a small product offering (here's to you In-and-Out!), so I jumped in line and then tried to figure out what I was in line for. Turned out to be german cheesecake, which is lighter than American cheesecake with a crust. It's made with quark, a yogurt-like fresh cheese not readily available in the US. It was sooooo good. It was so smooth, so light, and totally tangy, not sweet at all. This stand sold three flavors: classic, raisin, and cherry. I'm almost curious enough to go back to try the other ones. I've had Käsekuchen in Zurich a few times, but here it's much more cakey and dry, basically completely different in every way. I highly recommend this if you happen to be in Freiburg.
Second... We're always scanning the food booths to find something we haven't tried before. We found this super yum spätzle/sauerkraut combo at a sausage stand. It's truly inspired. We all loved it, even my 4yr old.