In a medium mixing bowl whisk together flour, almond flour and salt. Set aside.
In the bowl of an electric stand mixer fitted with the paddle attachment cream together butter, powdered sugar and brown sugar until well blended. Scrape down bowl.
Mix in one egg yolk. Then blend in second egg yolk with vanilla and almond extract. Scrape down bowl.
Add in flour mixture and mix until combined.
Divide dough into two equal portions and shape into round balls. Flatten each ball to a 6-inch disk. Wrap with plastic wrap and chill until more firm to roll, about 45 to 60 minutes.
Preheat oven to 350 degrees towards the end of dough is chilling (about the last 10 minutes). Line two 18 by 13-inch baking sheets with parchment paper.
Dust a clean work surface with a fair amount of flour. Remove one portion of dough from the fridge. Place on floured surface sprinkle top of dough with flour and roll to 1/6-inch thickness.
Cut into desired shapes using a cookie cutter (something like a circle, square, heart or star works well here. The size should be about 2 1/4 to 3-inches wide).
Transfer cut shapes to prepared baking sheet spacing 1-inch apart. You may find a bench scraper is helpful to transfer cut shapes to baking sheet.
Using a small star or heart cookie cutter (that's about 1 1/4- to 1 1/2-inches across) cut the shape from the center of half of the cookies on the cookie sheet (these will be the top, the other half should be left whole for the bottoms).
Chill cut cookies on baking sheet in fridge 10 to 15 minutes so they hold their shape well.
Bake in preheated oven until bottom edges are barely golden brown, about 9 to 11 minutes. Cool on baking sheet 5 minutes then transfer to a wire rack to cool completely.
Repeat this process of rolling, cutting and baking with the second disk of dough (also save scraps. Shake off excess flour, press them together and knead with your hands a little. Then chill as needed, re-roll and use up the dough. Scrapes can be reused once).
Once cookies are completely cool spread about 1 tsp jam over the whole cookies. Dust cookies with heart or star cut centers with powdered sugar then place those cookies over jam topped cookies.
Store cookies in an airtight container in the refrigerator. Tip: I like to wait to add the jam within a few hours of serving so the cookies are more crisp.
Good flavor options here include strawberry, raspberry, blueberry or apricot (strawberry freezer jam is my personal favorite).
Keep in mind you need to use a thick jam or it will just seep from the cookies (I've tried several brands here and those like Bonne Maman are too runny, Smuckers simply fruit is a tasty option thats nicely thickened).
If using raspberry jam I recommend using seedless.
You can also add 1/2 tsp ground cinnamon or a bit of nutmeg to the cookies. This would be tasty combo with blueberry jam.
The vanilla extract can be replaced with seeds of 1 vanilla bean (add these at the beginning with the butter and sugars).
For stronger sweet almond flavor you can increase almond extract up to 1 tsp.
Nutrition estimate based on a yield of 24 sandwich cookies.