Grate the onion and mix all the ingredients with the ground beef. Season well and let it rest in the refrigerator for at least 15 minutes, or longer if you have time.

Cut each loaf of bread halfway open.

Stuff each loaf generously so the bread is filled completely with meat.

Brush a baking tray with oil, then brush both sides of each stuffed loaf with oil or melted butter, depending on what you have available.

Preheat the oven. Bake the stuffed loaves for 10 minutes, then flip and bake for another 10 minutes. For extra flavor, heat a piece of charcoal until red hot, place it in foil with a drop of oil, and cover it with the bread to infuse a smoky aroma. Enjoy!