Combine the ★ ingredients in a sauce pan and heat over medium heat. Once it starts to bubble, reduce the heat.
In a separate sauce pan, combine the ○ ingredients, thoroughly dissolve the cornstarch, and heat over medium heat. While heating, use a whisk to combine evenly.
While whisking over heat, the mixture will stiffen into a paste as shown; when it does, remove from heat.
Gradually mix in the liquid from Step 1 to the saucepan from Step 3.
Thoroughly mix over low-medium heat. Until it thickens, it will tend to lump, so mix well.
Once the mixture turns yellowish and becomes pasty, add the nuts and rose water, and combine until even. Nuts are optional. If adding color, this is the time.
Grease a tray with olive oil, then pour into the tray. You can also pour them into baking molds, such as silicon molds. Chill well.
Once they cool and set, remove from the mold, then cut into cubes and dust with powdered sugar.
Story Behind this Recipe
I don't care much for the packaged lokums sold in Turkish souvenir shops, but ever since I tried the ones sold in a Turkish confectionery store, I've been enraptured. In an attempt to reproduce those lokums, I referenced recipes on non-Japanese sites, and came up with one using an easy-to-manage amount of ingredients.
The traditional way to make these is to add the paste from Step 3 into the liquid in Step 1. However, since it has a strong tendency to lump when done this way, I recommend the reverse--i.e. thinning out the paste with the liquid. You can also substitute the rose water with orange juice, pomegranate juice, or your choice of liquor for variation.