Straightforward gratin to use up a bunch of kohlrabi sitting in the fridge. The idea for the kohlrabi/cinnamon combination is from Le Menu, the rest is basically improv.
Brown some ground meat with a bit of salt. Add sliced leeks and let cook until the leeks soften. Add some flour and cook another couple minutes. Add red wine and reduce by half. Add some beef bouillon, cinnamon, nutmeg, sweet paprika, hot paprika, black pepper, and lemon zest. Let simmer for a bit. Layer the meat with thinly sliced kohlrabi in a gratin dish, finishing with meat. Sprinkle with a bit more cinnamon and nutmeg and let bake, covered, at 180C for 30 minutes. Top with Gruyere and bake, covered, another 10 minutes until the top is brown and bubbly.
This turned out quite nicely.