I bought a kohlrabi the other day. It was a monster. Literally, softball-sized. I was a little worried about it being fibrous and stringy, but it turned out to be just fine.
I didn't know what to do with it besides eat it raw, but I figured it would do well with an Asian-style dressing.
So I julienned up the kohlrabi and tossed it with some lemon juice. I don't know if kohlrabi turns brown, but I didn't want to take any chances. Which is kind of funny, really, since I added fish sauce and soy sauce later.
The dressing was a bit of sugar, some rice wine vinegar, soy sauce, and fish sauce, nuked just enough to dissolve the sugar. A few squirts of sriracha, and I was ready to go. Dump the dressing on the kohlrabi, toss a bit. Eat. Not bad, if I do say so myself.