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 you're using active yeast, activate it in a bowl with the lukewarm water and a teaspoon of the sugar.
Mix Dough: Add the vegetable oil, ½ cup of the sugar, 2 eggs, and half the lemon zest to the well. Using your hands, mix everything together, continuing to knead the dough for about 10 minutes. Alternatively, you can use a stand mixer on medium-low until the dough is smooth and pulls away from the sides of the bowl.
Let Rise: Transfer the dough to an oiled bowl, cover it with a clean towel or plastic wrap, and let it rise in a warm place until it doubles in size.
Make Cheese Mixture: In a medium bowl, mix the ricotta cheese, golden raisins, the remaining ½ cup of sugar, 1 egg, and the remaining lemon zest. Keep the cheese mixture in the fridge while waiting for the dough to rise.
Preheat Oven: Set your oven to 350°F (175°C) so it's ready when the buns are assembled.
Roll and Cut Dough: Once the dough has risen, roll it out to a long rectangle about ¼ inch thick. Use a pastry cutter to slice it into squares measuring 3 inches by 3 inches. Repeat with any remaining dough.
Roll It Out: Take each square and roll it out to about 6 inches square. It will be thin, but it will rise beautifully in the oven.
Assemble: Place 2 teaspoons of the cheese mixture in the center of each square. Fold over the corners to the center and pinch to seal. Repeat for all squares, ensuring they’re tightly sealed to prevent them from opening during baking.
Egg Wash: Beat the remaining egg and brush the mixture over the tops of the buns. Let them sit for another 10 minutes to rise slightly.
Bake: Bake the buns in your preheated oven for about 30 to 35 minutes, or until they’re golden brown and delightful.
Finish and Serve: Allow them to cool on wire racks, and if desired, sprinkle with powdered sugar before serving.