From the comments section here: a recipe for fermenting oatmeal using miso.
South River Porridge
1 cup rolled oats
2 cups water
2 teaspoons light miso (see note below)
Cook oatmeal in the evening 5-10 min., or until water is absorbed. (Do not use salt in the cooking.) Let oatmeal cool down to body temperature and then stir miso thoroughly into the warm cereal. Cover and let sit overnight at room temperature (about 70°). Reheat in the morning (without boiling) and serve.
Without imparting a noticeable taste of its own, the enzymatic power of the miso will liquefy the cereal, unlocking its essential nutrition, creating a wholesome sweet taste as it ferments overnight.
Other whole, rolled, cracked, or ground, cereal grains may be used, although cooking times will vary as necessary. Many pre-industrialized peoples fermented their grains to gain the most energy and nutritional strength from them.
Note: For this recipe it is necessary to use an unpasteurized light miso, rich in amylase enzymes. Choose South River Chick Pea, Sweet Tasting Brown Rice, Azuki Bean, or Sweet White Miso.
Creamy Oat Milk
Follow the same recipe above using 3 cups of water to 1 cup rolled oats. In the morning use a blender to transform the liquid porridge into a smooth milk. Strain if desired, heat and serve. Delicious with a touch of ginger!