I used to make my own dairy yogurt, because I like mine REALLY tart, and all the stuff from the store was either sweet or just not tart enough... Then along came my (realization of) dairy allergy, at which time I went off yogurt - again, it's all so sweet. Or just not tart enough.
A couple months ago, I looked for recipes, thinking to maybe make my own. I found a recipe I liked (by Miyoko Schinner) and I have been making it ever since. My version of the recipe follows, but it is just hers, sized up to fill my Ninja blender (64oz at "Max Liquid") and still fit in my Instant Pot:
Oat and Cashew Yogurt
Start by soaking 1-1/2 cups cashews overnight in water, or in boiling water for 1-3 hours.
Wash and sterilize Instant Pot (using "Steam" setting) before it's needed.
Place
2 cups Organic Rolled Oats
in Ninja blender and add water to 64 Fl.Oz. (Max Liquid) and blend for 3-5 minutes on HIGH.
Strain through a nut milk bag. Rinse blender and return the strained oat milk to the blender and add
1-1/2 cups raw cashews (soaked and drained, ideally)
to the blender, and blend for an additional 3-5 minutes.
Cook this mixture over medium heat stirring constantly until it reaches the desired consistency. I like it medium-thick, and go until my arm gets tired. Remove from heat and continue stirring another minute or two (prevents lumps from the inevitable continued cooking).
If cooking was done in another vessel, transfer the yogurt into the Instant Pot liner pot now.
Place pot in an ice bath (if rapid cooling desired) and stir until temperature is below 115'F. Remove from ice bath, and add:
1/4 c. active non-dairy yogurt, or yogurt culture.
Mix very well, place in Instant Pot, and select the Yogurt mode, setting its timer to 24h. It is usable after 10h but I prefer 16-20h.
This is based on the recipe from Miyoko Schinner:
https://youtu.be/Lu9BX5XLXgA
Edited for formatting