In a bowl, whisk together flour, almond flour, cinnamon, and salt. Set aside.
Beat butter and sugar until light and fluffy (~3 mins). Add egg yolk and vanilla; mix well.
Gradually add dry ingredients to the wet, mixing until a soft dough forms.
Divide dough in half, flatten into discs, wrap in plastic, and refrigerate for 1 hour.
Preheat oven to 350°F (175°C). Roll one dough disc to ¼-inch thickness on a floured surface.
Use a round cutter (2-3 inch) for the base cookies. Cut a small shape (heart, star, etc.) from the center of half the rounds.
Place on a parchment-lined tray and bake for 10-12 mins until edges are golden. Cool completely.
Dust the cut-out tops with powdered sugar. Spread 1 tsp jam on whole cookies, then press the tops gently.