I fried up a lil slice plain and it was very tasty! Great success. I missed shelling a few of the beans and would maybe cook them a tinnnny bit longer next time, but otherwise this is by far the easiest and most instant-gratification fermentation project I've ever done. I'm marinating some slices for TLT sandwiches later and froze most of it.
I really like doing napkin math so I did a cost breakdown and found out that per-batch, it is VERY cost effective to make it at home vs buying it (not to mention the possibility of experimenting with other beans and grains, which I'm really stoked about)
Spores: From Mycoboutique it's $35 for 50g which is the larger economy-sized package. You need about 4g of spores for 500g of dried soybeans, so ~$2.80 per batch.
Soybeans: At Bulk Barn prices they're $.27/100g, so that's $1.35 for 500g
So for one batch which starts with 500g dried soybeans and yields approximatedly 750g finished tempeh, that's $4.15 in raw materials (not including 30mL of white vinegar).
Comparitively, Noble Bean (local tempeh empire, which I learned is the largest tempeh maker in North America?? ) runs about $6 for a 240g brick these days. So that's $18 for roughly the same amount as I made at home for ~$4.15. Definitely worth it.