Linzer Cookies: 

1. In a stand mixer fitted with a paddle attachment (or a large bowl with a hand mixer), cream together the softened butter, sugar, and orange zest until light and fluffy, about 3-5 minutes. Add in the whole egg and vanilla extract and mix until combined, scraping well after each addition. 
2. In a separate large bowl, whisk together the all-purpose flour, almond flour, ground cinnamon, and salt. Add the dry ingredients to the wet ingredients and mix until just combined, scraping as needed.
3. Tightly wrap the cookie dough in plastic wrap, then refrigerate for at least 2 hours before rolling it out.
4. Preheat the oven to 350°F (177°C). Line a sheet tray with parchment paper or a silicone baking mat.
5. After the dough has chilled, lightly flour your countertop. Roll the cookie dough out to about a ¼-inch thickness, then cut out cookies approximately 2 1/2 inches wide. There should be 26-28 cookies. Then, use a smaller cookie cutter to cut out the middle of half of the cookie circles. 
6. Transfer the cookies to the prepared baking sheet, then bake them in the preheated oven for 10-12 minutes, or until lightly golden brown around the edges. Remove the cookies from the oven and let them cool for 5 minutes, then transfer to a wire rack to finish cooling. Make sure the cookies are completely cool before filling. 

Raspberry Jam: 

1. In a medium pot, combine the raspberries, sugar, lemon juice, and salt. Heat the mixture over high heat, stirring constantly with a heatproof spatula. Once the mixture starts to bubble up along the sides of the pot, reduce the heat to medium.
2. Cook the mixture for 10-12 minutes, or until you start to feel it thicken. To test if the jam is ready, I usually like to run my spatula along the bottom of the pot in a straight line. If it takes more than a second for the line to fill back up, the jam is usually ready. 
3. Once ready, remove the pot from the heat and transfer the jam to a heatproof container. I usually like to keep the raspberry seeds in the jam, but you can strain the jam through a sieve to get rid of the seeds if desired.
4. Let the jam cool completely at room temperature, then transfer to a piping bag. 

Assembly: 

1. Once the cookies have cooled, dust half of them (the ones without the middle) with powdered sugar. 
2. Pipe a teaspoon of raspberry jam in the middle of each normal cookie, then top with the cookies dusted with powdered sugar. Be sure not to overfill the cookies with jam or it will ooze out when you sandwich the cookies together. Enjoy!
3. Stored in an airtight container, these cookies will stay fresh at room temperature for up to 1 week.