You can find a handful by searching “low cadence” in the Workout library (best done on web). Short of that, you can make just about any workout low cadence on your own by simply doing so. I suggest considering the types of efforts you plan to use that cadence and apply LC there. It could be everything from Endurance thru Tempo or Sweet Spot, but should reflect your expected demands.
There is also my old thread that might be worth a look overall.