Preheat your oven to 350°F (175°C). Butter three 13x9-inch pans generously and line with parchment paper.

In a large mixing bowl, beat together the almond paste and granulated sugar until crumbly. Add unsalted butter and blend until smooth. Incorporate the egg yolks.

In a separate bowl, whip the egg whites until stiff peaks form. Gently fold into the almond mixture in thirds.

Divide the batter, leaving one-third plain and tinting two-thirds with red gel food coloring.

Pour the red batter into two pans and the white batter into the third. Bake for 10-12 minutes until firm.

Once cooled, spread raspberry jam on one red layer, top with white layer, and then another layer of jam before adding the final red layer.

Wrap the layered cookie stack tightly in plastic wrap and refrigerate for at least 4 hours.

Invert the chilled stack onto a cutting board, remove parchment, and melt the white chocolate chips to pour over the top. Let set before cutting into squares.