One thing you need to know about a sweet potato crust is that it isn’t a crunchy crust that you would get with pastry- the bottom stays firm enough to be able to cut a good slice, but is still essentially soft, however the edges do crisp up which add a lovely bit of texture and flavour.
A little lesson I learnt whilst making this…. don’t use a quiche tin with a removeable bottom! As the sweet potato crust is not water-tight (well, egg-tight), it will all seep out of the bottom if you try! Just a shallow round dish is perfect.