Add the all purpose flour, almond flour, cardamom and salt to a medium bowl and whisk to combine. Then set aside.
In a large bowl (preferrably using an electric mixer, though this can technically be done by hand), beat the butter and sugar together. You'll know it's ready when it's fully combined, light and fluffy!
Add the egg and vanilla to the butter and sugar and mix until fully incorporated.
Now add the flour mixture to the wet ingredients and mix until just combined. You'll want to be careful not to overmix here.
Once it's done, separate the dough into two halves and flatten each one into a disc. Cover the discs with plastic wrap (I know - ugh) and refrigerate for about an hour.
Preheat the oven to 350° and line a pan with parchment paper. Then roll the first disc out onto a floured surface (leave the second in the fridge until you're ready to use it). You'll want it to be about 1/8 of an inch thick.
When the dough has reached the desired thickeness, stamp out your cookies! Make sure you have the center cutout in place for half the dough and that it's removed for the other half so that you're left with an even number of each.
Carefully transfer each cookie to the pan and cook for 10-12 minutes, or until they've started to turn golden brown around the edges. Then transfer them to a wire rack to cool.
Repeat this process with the second disc! And don't forget to re-roll the dough scraps in order to reduce waste and increase your total cookie count. You can do this without re-refrigerating the re-rolled dough if you work quickly. If it's too warm, however, pop it back in the fridge for 20-30 minutes and try again.
Once all the cookies are baked and cooled, assemble them! Invert the bottom cookies and add about 1 tsp of jam (you can also eyeball it) to each. Then plop the cookies with the cutouts on top of them. Dust with powdered sugar if you'd like, and enjoy!