Whisk together flour, salt, sugar, and yeast.
Melt 3/4 cup butter, add milk, and pour into the dry mixture.
Knead until a shiny dough forms.
Cover with a dish towel and leave for 30 minutes.
De-stem and cut the persimmons up into small pieces
Heat the butter in a skillet and add the persimmons.
Coat with butter. Sprinkle with sugar.
Sauté until soft and staring to brown.
Remove from heat and set aside.
Line a baking sheet with parchment paper.
Roll out the dough on a lightly floured surface.
Sprinkle the caramelized persimmon and walnuts over the dough.
Fold and knead them into the dough.
Let rise for 15 minutes.
Roll the marzipan into a rope shape.
Pat out the dough into a rectangular shape and place the marzipan vertically down the middle.
Fold the sides over to cover the marzipan completely.
Transfer to the prepared baking sheet.
Cover with a dish towel. Let rest for 10 minutes.
Preheat oven to 350 F. Bake for 25 minutes or until the stollen turns golden around the edges.
Transfer to a wire rack and place it over the parchment-lined baking sheet.
Melt the remaining butter. Brush the tops and sides of the stollen while it is still warm.
Sprinkle with powdered sugar to coat the entire stollen.
Let cool completely.
Whisk together the powdered sugar and Contrineau.
Drizzle the glaze over the stollen and sprinkle the chopped walnuts over the glaze.
When the glaze has dried completely, transfer it to a platter, cut, and serve.