Soak the gelatin in 2 tablespoons of water. Squeeze the lemon (it's better if you add a bit of the pulp as well).
Pour the water, umeshu and honey into a pot, and turn on the heat. When it comes to a boil, turn the heat down and simmer for 2 minutes to evaporate the alcohol.
Add gelatin and stir well, then add lemon juice. Pour into cups, and let cool in the fridge until set.
Story Behind this Recipe
I enjoy drinking warmed umeshu with lemon juice and honey, and I wondered if it might turn out well as a gelatin dessert, so I came up with this recipe.
If you use umeshu that's not so sweet, add more honey. If you prefer a sour taste, add more lemon juice, about 1 1/2 to 2 tablespoons. This recipe makes soft jelly, so if you'd prefer it firm, reduce the amount of water or umeshu by about 50 ml.