Preheat oven to 350°F. Line two baking sheets with parchment paper.
Cream butter and sugar in a large bowl until pale and fluffy, about 2 minutes.
Beat in the egg, vanilla, and almond extract until smooth.
Whisk flour, almond flour, baking powder, and salt in a separate bowl.
Add dry ingredients to the butter mixture. Mix on low until a soft dough forms.
Chill the dough 15 minutes to make shaping easier.
Scoop 1-tbsp portions, roll into balls, and space 2 inches apart on sheets.
Press a deep indent in each ball with a thumb or 1/2-teaspoon measure.
Fill each indent with a scant 1/2 teaspoon raspberry jam. Sprinkle edges with sliced almonds if using.
Bake 10–12 minutes, until edges are set and just turning golden.
Cool 5 minutes on the sheet, then transfer to a rack. Dust with powdered sugar once fully cool.