Line two baking sheets with parchment paper and set aside.
Separate eggs yolk from white and set the egg white aside.
In a large bowl, or the bowl of your mixer, add softened butter, egg yolk, sugar and 1 teaspoon vanilla extract.
Using an electric hand mixer beat the mixture until light and fluffy.
Add flour and salt and mix well until combined.
With a fork whisk egg white with the remaining ¼ teaspoon vanilla extract.
Scoop dough into balls (about 18g) and roll between your hands until smooth and rounded.
Dip balls into egg white then roll into chopped almonds.
Place dough balls 2 inches apart on your cookie sheet.
Use your thumb, or the back of a measuring teaspoon, gently press to make an indent in the center of each cookie.
Freeze cookies sheet for at least 30 minutes to firm up a bit.
Preheat your oven to 325F and place your jam in a bowl.
Stir jam so it is no longer firm and easily scoopable.
Take the first sheet out and fill each cookie with the jam.
Bake in the center of the preheated oven for 13-15 minutes.
Remove sheet from oven and allow cookies to cool completely on the baking sheet.
Bake the other sheet and allow it to cool down completely as well.