In a large bowl, mix the flour, salt, and sugar. Make a well in the center.
Gradually add the warm water, mixing until a dough forms. Knead the dough on a floured surface for about 5 minutes, until smooth and elastic.
Divide the dough into 4 equal portions and roll each portion into a thin rectangle (about 12x8 inches / 30x20 cm).
Brush each rectangle of dough with melted butter or margarine.
In a small bowl, mix the honey, date syrup (or molasses), and vegetable oil.
Spread a thin layer of the honey mixture over each rectangle of dough.
Roll each rectangle tightly from one edge to form a log. Pinch the ends to seal.
Place the rolls on a baking sheet lined with parchment paper, seam side down.
Cover with plastic wrap or a clean kitchen towel and let the rolls rise for about 1 hour.
Preheat your oven to 250°F (120°C).
Bake the rolls in the preheated oven for 8-10 hours, or overnight. This low and slow cooking method allows the rolls to develop a rich, caramelized flavor.
Allow the Jachnun to cool slightly before slicing.
Enjoy your meal!