
To make the jelly, put the 55 grams evaporated cane sugar and 4 grams agar-agar powder into a pot and then add the 4 cups coffee. Put the pot on the stove and stir it while bringing it to a boil.
When the mixture comes to a rolling boil, remove it from the heat and pour it into an 8 x 8-inch mold. Let this cool to room temperature, cover it, and put it in the refrigerator to fully set.
To make the sauce, add the 1/2 cup heavy cream and 1/4 cup sweetened condensed milk to a bowl and stir the mixture together until it's evenly combined. Keep the cream chilled in the fridge until you're ready to serve it.
When the coffee jelly has been set, unmold it by inverting it onto a cutting board. You can run a toothpick along one edge of the mold to release any suction that may be holding it in.
Cut the coffee jelly into bite-sized cubes and serve it in glass cups or bowls, drizzled with the sweet cream.