Preheat your oven to 350 degrees.

Make a simple syrup by placing the water and sugar in a microwave-safe bowl. Heat in the microwave for 90 seconds or until the sugar is completely dissolved. Stir in almond extract.

In a bowl, combine almond flour, softened butter, granulated sugar, egg, almond extract, and vanilla extract. Mix until well combined and smooth.

Cut each croissant in half horizontally to create a pocket for the almond filling. Lightly brush the inside of the croissant with simple syrup.

Generously spread the almond filling on the bottom half of each croissant. Reserve a small amount of almond filling for the top of the croissants. Place the top half back on, creating a sandwich.

Spread a small amount of almond filling on the middle top of each croissant. Sprinkle sliced almonds over the top of each croissant, pressing them gently into the almond filling.

Place the filled croissants on a parchment paper lined baking sheet and bake in the preheated oven for 12-15 minutes or until the tops are golden brown.

Allow the almond croissants to cool slightly before dusting with powdered sugar for an extra touch of sweetness.