In a mixing bowl or food processor, combine the marzipan, almond flour, powdered sugar, almond extract, lemon juice, and egg white. Knead until a thick, tacky dough forms, then chill for at least 30 minutes.

Remove the dough from the fridge and preheat your oven to 350°F (175°C). Shape the dough into 1-inch logs tapering the ends.

Brush each log lightly with egg white and roll them in sliced almonds until fully coated.

Bend each log into a crescent shape and place on a parchment-lined baking sheet.

Bake the Mandelhörnchen for about 10-15 minutes until the almond tips turn golden brown.

Remove from oven and allow to cool completely on the baking sheet before transferring to a wire rack.

Melt chocolate and dip one end of each cooled almond horn into the chocolate.

Place the chocolate-dipped Mandelhörnchen on parchment paper and allow the chocolate to harden completely.

Store in an airtight container; they can last up to two weeks.