Preheat oven to 350 F. Prepare baking sheet by lining it with parchment paper.
In medium mixing bowl whisk together all-purpose flour and salt. Set aside.
With a help of a stand mixer and paddle attachment on cream butter, both sugars, and vanilla for about 5 minutes.
Add 1 egg and mix to incorporate lightly. It will start to separate but do not stress about it. It will all come together once we start adding dry ingredients.
With mixer on low speed add half of your dry ingredients and mix to incorporate. Stop the mixer and scrape the sides and the bottom of your bowl. Add rest of the dry ingredients and mix just until it incorporates.
Scoop enough cookie dough to form 1” ball (about20-25g). Roll the ball and place it on the prepared baking sheet lined with parchment paper.
Immediately, with the help of your thumb or back of a small round spoon form an indent. Dip the spoon/thumb into some flour so it doesn’t stick to the cookie dough. Repeat for the rest of the balls. Space the balls about 2-3” apart.
Place your jam into the pastry bag or a small Ziplock bag. Cut a little opening on one of the corners of the bag and fill in cavities of the cookies. When cutting a Ziplock bag corner be sure to discard the little cut piece immediately, so it does not get into your cookies.
Bake at 350 F 15-20 minutes, or until the edges start to get golden color.
Once they bake, they soak in a little bit of jam. You can add some more if desired.
To decorate melt some white chocolate and drizzle over your cooled cookies. Let set.
Store cookies in an airtight container for up to 1 week.
Use a preheated oven.
Whisk jam well before adding into the cookie for easier application.
Use real butter. Do no substitute with margarine or butter substitutes.
Use cold butter so the dough holds up and doesn't spread.
Be sure all your ingredients are up to room temperature.
Place your dough balls on a baking sheet lined with parchment paper, for easy removal and cleanup.
You can use your thumb or back of a spoon to make indents on the dough.
The cookies can soak up some of the jam during baking, so feel free to top them up halfway through the cook, if needed.
Keep an eye on the edges of the cookies, when they turn golden brown they are done.