Preheat the oven to 325 degrees F. In the bowl of an electric stand mixer, beat butter, 1 cup of the powdered sugar, lemon zest, 2 tablespoons of the lemon juice until pale and fluffy, about 3 minutes. Gradually add the flour and salt, and mix on low speed until just combined.

Line a baking sheet with parchment paper. Use a small ice cream scoop or a tablespoon to scoop the dough and roll into 1-inch size balls. Place on the prepared baking sheets. Freeze the dough balls for 15 minutes until the dough is firm. This will help prevent the cookies from spreading, don't skip it!

Straight from the freezer, place the cookies in the oven and bake for 10 minutes. Remove the cookies from the oven, and use your cardboard cut-out heart to press directly into the center of each cookie to indent. Use a small pairing knife to lift the heart after pressing firmly down. You can also use the back of a spoon or your thumb for a traditional thumbprint. Return the cookies to oven, and bake for another 15-17 minutes. They should not be golden brown. Allow to cool completely. Place 1-2 tablespoons of powdered sugar in a small sieve, and dust the cookies with the sugar.

Meanwhile, make the pink glaze. In a small bowl, mash 1 single raspberry with the back of a fork. Add the remaining 1 cup of powdered sugar to the bowl, and the last tablespoon of fresh lemon juice, plus 1 tsp water. Mix until smooth. You can spoon the glaze into the center of each cookie. OR for more accuracy, place the glaze in a small zip top sandwich bag, and snip the corner, creating a small piping bag to fill each indentation.

Optional: sprinkle the crushed freeze dried raspberries for a little additional decoration.