I made some food that was supposed to be for nerite snails--Ha! They never touch it, but my cory cats love it! The recipe started with a small jar of baby food (green peas or green beans), and to that I added one packet of unflavored gelatin. I mixed the two together in a small bowl, and then microwaved it for one minute. After that, I added other kinds of fish food (thawed bloodworms, brine shrimp, flake food--whatever was on hand). I also added some thawed, chopped-up spinach (make sure it's salt-free) and some crushed up, cleaned egg shell (again, this was supposed to be for snails & I thought they'd like the calcium). Anyway, I poured it on a plate and put it in the refrigerator. After it set, I cut it into little cubes and froze them all in a ziplock bag.
To feed the cories, I drop a frozen piece into the tank (always in the same corner of the tank), and it immediately sinks to the bottom. I think the cories actually anticipate it; they congregate in that part of the tank when it's feeding time. they seem to love it.