Once your larger rectangles are ready, take a knife or pizza cutter and cut the rectangles into smaller triangles (zig-zag pattern) from top to bottom.
Fold the bottom of each triangle and roll it into a croissant-like shape.
Place all your croissants on the baking sheet and brush the tops with the beaten egg.
Place in the oven for 20 minutes.
While the croissants bake, heat sugar and water over medium flame. Stir continuously to dissolve all the sugar. Remove from heat, let it cool, and add almond extract. This makes your almond syrup.
When 20 minutes are up, take the croissants out of the oven and brush them generously with the almond syrup. Next, take the sliced almonds and press them onto the croissants as well.
Place the croissants back in the oven and bake for another 5 to 10 minutes until the surface starts to become golden, which means the almonds are toasting.
Carefully cover the croissants with foil, so they don't burn and bake for another 10 minutes to ensure their insides are done.