These are really impressive and delicious cookies to make if you decide to venture into these deep baking waters! You might want to give yourself a day or 2 to make these as they take quite a bit of time.
Blend dough ingredients in a mixer. Add milk as needed.
Split the dough into 4 balls and cover. Refrigerate overnight
In a saucepan over medium heat, add the prunes sugar and water.
Simmer uncovered until the prunes are soft and jammy, about 30 minutes
Remove from heat and let cool before using.
Roll dough out into a a large sheet and cut into 3-inch squares.
Place a teaspoon of filling in the center.
There are many different ways to fold these but the easiest is to take each corner and fold it to the center, to form a pinwheel.
Place on an ungreased baking sheer and bake at 400ºF for 5-10 minutes