Soak the raisins in warm water to plump them up.
Mix the yeast with 1/3 cup warm milk (about 100 milliliters) and a little flour to make a starter dough. Let it rest until it doubles in size.
Combine the remaining flour, salt, sugar, eggs, and the rest of the milk. Knead for 15 minutes to aerate the dough well.

Add the softened butter and mix thoroughly.
Then add the starter dough and knead for a few more minutes until the dough pulls away from the sides of the bowl.
Cover with a cloth and let rise for 1 hour in a warm place (such as near a radiator).
Gently press down the dough to return it to its original volume.

Add the raisins and mix.
Generously butter a kouglof mold, making sure to get into the grooves. Place a whole almond in each groove. Add the dough and let it rise until it reaches the top of the mold.
Bake for 50 minutes at 350°F (180°C). If the top browns too quickly, cover with parchment paper.
Remove from the mold onto a wire rack and dust with powdered sugar.