Dissolve Yeast: In a big bowl, add the flour and form a well in the middle. Crumble up the fresh yeast and add it in the well. Pour the water over the yeast and stir it up until the yeast dissolves. If using active yeast, activate in a bowl with the lukewarm water and a tsp of the sugar.x
Mix Dough: Add the oil, ½ cup of the sugar, 2 eggs and half the lemon zest to the well. Using your hands mix everything together and continue kneading the dough for about 10 minutes. Alternatively you can do this in your stand mixer and mix on medium low until the dough is smooth and comes clean from the sides of the bowl.
Let Rise: Place the dough in an oiled bowl, cover it up with a clean towel, or plastic wrap and let it double in size, in a warm place.
Make Cheese Mixture: While the dough is rising, we can make the cheese mixture. In a medium bowl, add the ricotta cheese, raisins, remaining ½ cup of sugar, 1 egg, remaining lemon zest and mix it all together. Place the cheese mixture in the fridge while the dough is rising.
Preheat oven: Preheat oven to 350°F.
Roll and Cut Dough: After the dough has doubled in size, roll it out in a long rectangular so that it's about ¼ inch in thickness. Using a pastry cutter cut it into squares that are 3" x 3". Repeat with remaining dough.
Roll it Out: Take each square and roll it up until it's 6" x 6", it will be quite thin, but don't worry as it will rise quite a bit more.
Assemble: Place 2 tsp of the cheese mixture in the center of each square. Fold over each corner of the square over to the middle and pinch in the middle to make the dough stick. Now fold each newly formed corner over to the middle again and pinch it in the middle. Make sure you pinch it well, otherwise the dough will open up. Repeat with remaining dough and cheese mixture.
Egg Wash: Beat the remaining egg and brush the cheese buns with it. Let them sit out for another 10 minutes so they rise a bit more.
Bake: Bake in the oven for about 30 or 35 minutes, or until golden brown.
Finish and Serve: Cool on wire racks and sprinkle with powdered sugar if preferred.