To Make the Cookies:

1. Preheat the oven to 350 degrees.
2. In the bowl of an electric mixer fitted with the paddle attachment, mix together the butter, the sugars and the vanilla on medium-high speed until light and fluffy, about 3–5 minutes.
3. In a medium bowl, sift together the flour and salt, then add them to the butter-and-sugar mixture.
4. Mix on low speed until the dough starts to come together. Scrape down the sides of the bowl with a rubber spatula, as needed.
5. Dump the dough onto a surface dusted with flour and shape into a flat disk. Then wrap the disc in plastic and chill for at least 30 minutes.
6. Roll the dough 1/4-inch thick and cut 2 3/4-inch rounds with a plain or fluted cutter.
7. With half of the rounds, cut a hole from the middle of each round with a design-shaped cutter of your choice.
8. Place all the cookies on a baking sheet lined with parchment paper and chill for 15 minutes.
9. Then bake the cookies for 20 to 25 minutes, just until the edges begin to brown.
10. Allow the cookies to cool to room temperature before trying to fill.

To Make the Buttercream:

1. In a medium bowl, beat butter with a mixer at medium speed until creamy.
2. Gradually add the confectioners’ sugar and salt, mixing well after each addition.
3. Add the strawberries mixture, and beat until incorporated.
4. Adjust the color by adding food coloring, if desired.

To Assemble the Cookies:

1. When the cookies are cool, spread a thin layer of the buttercream on the flat side of each solid cookie.
2. Next, dust the top of the cut-out cookies with confectioners’ sugar.
3. Press the flat sides together, with the buttercream in the middle and the confectioners’ sugar on the top.