01 - 
                Line up your baking sheets with parchment paper. In a medium-sized bowl, mix the flour, cornstarch, and salt together with a whisk. Put the bowl aside for later.
              
              
              
                02 - 
                Throw the softened butter, packed brown sugar, and granulated sugar into a large mixing bowl. Beat everything together for a couple of minutes until the mix looks airy and fluffy.
              
              
              
                03 - 
                Mix the egg yolk, vanilla, and almond flavoring into the sugary butter. Gradually add in the dry mix you set aside earlier, stirring until you’ve got smooth dough.
              
              
              
                04 - 
                Form little balls of dough, about a spoonful each. Flatten them gently into hearts and press a small dip in the middle with your thumb or a spoon. Lay them on the baking sheets and pop them in the freezer to firm up for 30 minutes.
              
              
              
                05 - 
                Heat the jam either in a microwave or on the stove until it’s a bit runny. Spoon about half a teaspoon into the indent in each cookie.
              
              
              
                06 - 
                Set your oven to 375°F to preheat. Bake the cookies for around 10–12 minutes, or until the edges turn golden. Let them sit on the baking sheet for a few minutes before transferring them to a rack to finish cooling.