Linzer Cookies are a delightful jewel in the crown of traditional European desserts, originating from the Austrian city of Linz. It's essentially a sandwich cookie composed of two buttery, hazelnut-enriched shortbread-like rounds. Made with flavorful hazelnuts, these cookies can typically be found in the very best Austrian Pastry shops. The top half is a decorative cut-out showcasing the glistening jewel-toned jam nestled in the middle. The cookie's surface is dusted with a snowy sprinkle of powdered sugar, making it not only a treat for the palate but also a visual delight. When bitten into, a Linzer Cookie offers layers of textures and flavors: the nutty richness of the cookie pairs perfectly with the sweet and tangy burst of jam in the center.
If using raw hazelnuts toast them first by placing them on a cookie sheet in a preheated oven for 13-14 minutes. Let cool.
Place 1/2 of measured all-purpose flour along with hazelnuts in a food processor and mix until hazelnuts are fine as meal. Add remaining flour, baking powder, and cinnamon and set aside.
Mix butter until light and fluffy, add sugar followed by egg, salt, and orange zest. Mix until light and well combined.
Add dry ingredients and mix very briefly until just combined.
Press flat onto a plastic food film lined cookie sheet and place in the freezer until firm, about 30 minutes.
This dough can be a challenge to roll since it easily sticks, however rolling lightly floured dough between 2 sheets of thick plastic (use food storage bags) works great.
Roll chilled dough 1/8-inch thick. If it gets too soft, keep it between plastic sheets and freeze it a little longer. Cut into rounds about 1 1/4-inch wide and place on parchment lined cookie sheets. Cut 1/2 of the circles with a second cutter to obtain a ring shape, and then place on the circle.
Bake until light golden, about 13-15 minutes. Allow to cool.
Fill with lemon curd or good quality jam of choice. Sprinkle with powdered sugar.