In a bowl, pour the buttermilk and add the yeast. Let it dissolve completely. Then, add the sifted flour. Mix everything well with your hands (or using a stand mixer) until you get a smooth, soft, and uniform dough.

Now, add the butter. Knead for a long time, until the butter is fully absorbed into the dough.

Cover the bowl with plastic wrap and place it in the oven (turned off, but with the light on) to rest for 30 to 40 minutes.

Prepare the mold (or molds if you want smaller ones). Line them with baking paper.

On a lightly floured surface, roll out the dough with your hands or a rolling pin until you form a rectangle. The short side should be as wide as the long side of the mold.

Starting from the short side, roll the dough tightly into a log shape. Place the roll into the prepared mold, seam-side down. Let the dough rise in the oven (turned off, with the light on) for about 1/1.5 hours or until the dough rises past the edges of the mold.

After the rising time, bake the bread. Preheat the oven to 180°C (356°F) fan or convection setting and bake for 30 to 45 minutes, or until the bread is fully cooked and golden brown on top.

Once baked, remove the bread from the oven and let it cool completely. You can store the whole loaf in a tightly sealed plastic food bag for 4-5 days