In a large bowl, beat the softened butter, light brown sugar, and granulated sugar together until the mixture is light, fluffy, and pale—this usually takes 2-3 minutes with an electric mixer. This creaming process incorporates air into the dough, which helps create the tender, crisp texture that makes linzer cookies special. Once fluffy, add the vanilla extract and beat until fully incorporated.

In a separate bowl, whisk together the all-purpose flour, almond flour, cornstarch, cinnamon, and salt. I like to sift the powdered ingredients together rather than just stirring them—this ensures the cinnamon and cornstarch are evenly distributed throughout, which gives you consistent flavor and texture in every bite. Set this mixture aside until you're ready to combine it with the butter mixture.

Add the dry ingredient mixture from Step 2 to the creamed butter mixture from Step 1 and stir until just combined—don't overmix, as this can make the cookies tough. Divide the dough in half, shape each portion into a flat disc, wrap tightly in plastic wrap, and refrigerate for at least 30 minutes. The chilling time allows the gluten to relax and the flavors to meld, which prevents the dough from shrinking during baking and makes rolling easier.

Preheat your oven to 350°F (175°C). Remove one disc of chilled dough and roll it out on a lightly floured surface to about ⅛ inch thickness—this thin, even thickness is crucial for getting that signature crisp texture. Keep the second disc chilled until you're ready to use it.

Using a 2½-inch round cutter, cut circles from the rolled dough. You'll need an even number of circles total. For half of them (the 'bottom' cookies), place them directly on a parchment-lined baking sheet. For the other half (the 'top' cookies), use a smaller cutter or a sharp knife to cut out a shape from the center—a small circle, heart, or star window works beautifully. Place these cut-out cookies on the same baking sheet, spacing them about an inch apart. Repeat the rolling, cutting, and placement process with the second dough disc.

Bake all cookies (both the solid bottom pieces and the cut-out top pieces) at 350°F (175°C) for 9-10 minutes, until the edges are light golden brown. The cookies will still feel slightly soft when warm, but they'll firm up as they cool. Remove from the oven and let the cookies cool completely on the baking sheet for at least 10 minutes before handling—I find that cookies are less likely to break apart when assembling if they're completely cooled.

Dust the cut-out cookies with powdered sugar, covering the decorative windows generously. Spread about a teaspoon of raspberry jam onto the flat side of each solid bottom cookie, then carefully press a cut-out cookie on top, jam side down, to create a sandwich. The jam should peek through the window of the cut-out cookie for a beautiful, festive presentation.