In a medium bowl, sift together the flour, cocoa, baking powder and kosher salt. Set aside.
In a large bowl, cream together the butter and sugar until smooth. Beat in the vanilla, egg, and egg yolk. On low speed or by hand, gently stir the sifted ingredients into the butter-sugar mixture until they form a soft dough. Divide dough into 2 pieces, flatten each slightly into disks, and wrap tightly in plastic wrap. Refrigerate for 1 hour or overnight.
When ready to bake, place rack in the center of the oven (or upper and lower thirds to bake two batches simultaneously) and preheat oven to 375 degrees F.
Line baking sheets with parchment paper and set aside. On a lightly floured surface or between two sheets of wax paper, roll the dough out to a 1/4-inch in thickness. The dough will be sticky, so spread additional flour on the rolling surface as needed. Cut rolled dough into heart shapes with cookie cutters. Place cookies 1 1/2 inches apart on prepared baking sheets.
Bake for 9 minutes, until just dry at the edges. If baking two sheets at once, rotate positions halfway through. Allow cookies to cool on baking sheet for 5 minutes, then remove to a wire rack to cool completely.
Prepare Raspberry Cream Cheese Filling: Beat the cream cheese, butter and jam together until smooth. Beat in the almond extract and food coloring. Reduce speed to low, then sift in powdered sugar a little at a time. Once sugar is incorporated, increase mixer speed to high and beat until the mixture is smooth. Refrigerate filling until the cookies have completely cooled and are ready to be filled.
Fill and assemble cookies: With an offset spatula or a piping bag, spread or pipe desired amount of filling on the back side of one cookie, leaving a small margin at the edges. Top with a second cookie to create a “sandwich.” Enjoy immediately.
The Raspberry Cream Cheese Frosting will become soft as it sits at room temperature, so fill just before serving. The cookies and frosting will keep separately (cookies in an airtight container at room temperature; raspberry cream cheese frosting in the fridge) for about 10 days.