I tried this recipe for fermented oatmeal from thekitchn.com: Soak 1 cup oatmeal in 1 cup water with 2 tbsp yogurt overnight for 8-24 hours.
With an overnight soak, the taste was about what you’d expect from oatmeal and yogurt, not exceptionally earth-shattering.
I liked it better the second time I tried it, with a 24 hour soak using kefir. The flavor wasn’t sour at all, but a little extra nutty and complex.
Nora refused to eat it until my mom mixed it with some full-fat, plain yogurt. I might want to try coconut milk sometime, just to change things up for both her and me.