I have both 4 and 8 ounce jars. I have only scratched the surface of the list of things they are good for. Here is one I am working on with the 4 oz jars containing eggs and something else, in this case, crab meat.
These crab bites came cleanly out of the jar. I used cooking spray, spritzing the inside of the jar and doing a quick wipe with a saturated paper towel to make it even and so all the surfaces were covered. The cooking was 165F for 4 hours. Two would probably have done the trick.
To get 9 servings I used a pound of crab meat, six eggs, onion flakes and some panko. There are as many possibilities and there are types of omelettes.