Preheat the oven to 325°F (163°C). Line two baking sheets with parchment paper.
In a large bowl, cream together the softened butter and granulated sugar until light and fluffy, about 3-4 minutes.
Add the vanilla extract and mix to combine.
Gradually add the all-purpose flour and salt to the butter mixture, mixing on low speed until the dough just comes together.
Turn the dough out onto a lightly floured surface and knead gently until smooth.
Roll the dough out to about 1/4 inch (6 mm) thickness.
Using a round cookie cutter (about 2 inches in diameter), cut out an even number of cookies.
Place half of the cookies on the prepared baking sheets.
On the remaining half of the cookies, use a smaller round cutter (about 1 inch in diameter) to cut out a hole in the center to create a window.
Transfer all cookies to the baking sheets, spacing them about 1 inch apart.
Bake in the preheated oven for 20-25 minutes, or until the edges are lightly golden.
Remove from the oven and allow the cookies to cool completely on the baking sheets.
Once cooled, spread about 1 teaspoon of raspberry jam on the bottom side of each whole cookie.
Top each jam-covered cookie with a cookie that has the cut-out window, pressing gently to sandwich them together.
Serve immediately or store in an airtight container.