After measuring the Irish moss, rinse it 3 or 4 times in water to remove the salt and sand; drain well.
Cover with filtered water and let sit at least overnight. The Irish moss will double in size and become translucent, at which point it's ready to use.
Drain the Irish moss and cut into small pieces; put in the blender with 1/2 C. (125 ml) filtered water. Blend on high about 3 minutes, until it's a smooth, thick gel with no visible pieces of moss left.
Chop the dates into small pieces, discarding the date pits. Warm the coconut oil enough to liquify it.
Add the almond milk, dates, agave syrup, cocoa powder, vanilla, and salt. Blend until smooth.
With the blender still running, slowly add the lecithin. Continue blending, adding the coconut oil in a steady stream.
Pour into a bowl or your serving dishes and refrigerate about an hour until set. Top with berries.