Mix the lukewarm milk with the yeast and set aside for 5-6 minutes.
Mix together the sugar, soft butter, eggs, lemon zest, flour, and salt and knead into an elastic dough.
Let the dough rise for one hour or until it doubles in volume.
With a spatula, mix all the ingredients for the filling except the raspberries.
Once the dough has risen, roll it out into a 7-8 mm ( ~1/4 - 1/3 - inch) thick rectangle.
Cut the dough into twelve 10-12 cm ( ~4-5-inch) squares.
Place a spoonful of the cheese filling in the middle of each square, place 3-4 raspberries on top, and bring the corners of the square to the center, sticking them together over the filling.
Let the buns rise in the pan for another 20 minutes, then brush with egg yolk mixed with 3-4 tablespoons of milk.
Bake the buns in a preheated oven at 200° C/392 ° F for 20 minutes.
After baking, dust with sugar and serve hot or cold!