Irish moss is a seaweed. It has many uses. This is a Rawfully Tempting article about Irish moss.
How to make Irish moss paste, or gel.
Grab a small handful of dried Irish moss.
Put it in a medium bowl and cover with cold water. Swish it around once in a while and let it soak for 4 hrs, until it is about tripled in size.
Drain the moss into a sieve, discard the water. That it reconstituted ocean water. You can really smell the ocean during the initial soak but once it's cleaned and blended the smell is not noticeable.
There are little bits of vegetable matter and sand and strings of plastic. It takes a while to pick it all out. Take your time and clean it well, rinsing and picking in between all the little branches. Anywhere you see a dark spot its probably a little piece of stuff you want to pick out.
Once you have the moss picked clean, rinse it one last time and discard the rinse water.
Put moss in high speed blender with 2 cups water for every 1 cup moss.
Blend until there are no more chunks. Add a little more water if needed to blend. Let the blender take breaks and cool off so the gel doesn't overheat and cook.
Transfer your gel to a jar or jars with tight lids and store in the fridge for three weeks. You can use it in desserts and smoothies, as an egg sub in baking as a moisturizer and facial mask and many other applications.
Check out the article at Rawfully Tempting, it's very informative.