In a large bowl, mix the all-purpose flour, melted butter, salt, and a mixture of the warm water and 1 tablespoon of orange blossom water. Knead gently until a smooth, elastic dough forms. Wrap in plastic and let it rest for 20 minutes.

To make the filling, combine the almond flour, granulated sugar, cocoa powder, orange zest, softened butter, and the remaining 2 tablespoons of orange blossom water in a bowl. Mix by hand until it forms a moist, moldable paste.

Take small walnut-sized portions of the filling and roll them into small logs roughly 3 inches long with tapered ends.

Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

On a lightly floured surface, roll out the dough very thinly (about 1/8 inch thick).

Place a log of filling near the edge of the dough. Fold the dough over the filling to cover it completely, pressing down around the filling to seal it and remove air pockets.

Using a pastry cutter or knife, cut the dough around the sealed filling, leaving a small border. Curve the pastry into a crescent moon shape (a gazelle horn) and place on the baking sheet.

Repeat with the remaining dough and filling, spacing the pastries about an inch apart on the sheet.

Bake for 12-15 minutes, until the dough is set and very lightly golden (do not let them brown too much).

Allow the cookies to cool on a wire rack. Dust with powdered sugar before serving if desired.