Preheat oven to 350°F. Line two baking sheets with parchment.
Whisk flour and salt together in a small bowl; set aside.
Cream softened butter and 1/2 cup sugar until pale and fluffy, about 2 minutes.
Beat in egg yolks, vanilla, and almond extract until smooth.
Add dry ingredients to the bowl and mix on low just until a soft dough forms.
Chill dough 15 minutes to firm slightly for easier shaping.
Scoop 1-tbsp portions, roll into balls, then roll each ball in the extra sugar.
Arrange on sheets, spacing 2 inches apart. Press a deep well in each with your thumb or the back of a 1/2-teaspoon.
Stir jam to loosen. Spoon a small mound into each indentation, about 1/2 teaspoon.
Bake 11–13 minutes, until edges are set and just turning golden. Cool 5 minutes, then move to a rack to cool completely.