Ingredients:
The Buttery Shortbread Dough:
1 cup (227g) unsalted butter, softened
¾ cup (150g) granulated white sugar
1 large egg
1 tsp vanilla extract
2 ½ cups (310g) all-purpose flour
½ tsp baking powder
½ tsp salt
The Filling:
½ cup seedless raspberry jam (or preserves)
1 tbsp cornstarch (the secret to preventing the jam from leaking out!)
Steps:
Cream the Base: In a large bowl, beat the softened butter and sugar together until light and fluffy (about 3 minutes). Add the egg and vanilla extract; beat until well combined.
Add Dry Ingredients: In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add this dry mixture to the wet ingredients on low speed. Mix just until a soft dough forms.
Roll Out: Divide the dough in half. Roll each half between two sheets of parchment paper into a rectangle that is about ¼-inch thick.
Prepare the Jam: In a small bowl, whisk the raspberry jam with the cornstarch. This thickens the jam so it stays perfectly inside the spiral while baking.
Spread & Roll: Spread a thin, even layer of the jam mixture over the dough rectangles, making sure to leave a small border at the edges. Starting from the long side, tightly roll the dough up into a log.
Chill (Crucial Step!): Wrap the logs tightly in plastic wrap. Refrigerate for at least 2 hours (or freeze for 30 minutes). If the dough is too soft, the beautiful spiral will smoosh when you try to slice it.
Slice: Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Use a very sharp knife to slice the cold log into ½-inch thick rounds.
Bake: Place the cookies 2 inches apart on the prepared baking sheet. Bake for 10–12 minutes until the edges are just barely golden. Let them cool completely on the baking sheet so the shortbread and the caramelized jam can firm up!
