We made this a lot when I was growing up. The jelly was melted in half the normal amount of water first and left to cool. The evaporated milk (not condensed) was beaten to a froth in batches - probably because using a hand rotary whisk. Then the cooled jelly was added gradually to the frothy milk, while beating and finally left to set. One can of milk and one jelly made a huge bowl of “jelly fluff”
Giving my pots a bit of a boost after the winter

