These Jam Sandwich Cookies are made from two buttery layers of shortbread-style cookies sandwiched together with sweet jam and dusted with icing sugar.
Add the softened butter and sugar to a food processor. Pulse until well combined and there are no lumps of butter.
First, add the whole egg to the creamed mixture with the food processor running, and pulse until combined. Then add the egg yolk and vanilla and pulse until well combined.
Sift together the flour and salt and add this flour mixture to the egg and butter mixture all at once. Pulse until a dough forms, do not overmix.
Remove the dough from the food processor, cover it in plastic wrap, and refrigerate for an hour.
Preheat the oven to 160°C (320°F) and line two large baking trays with parchment paper.
Remove the chilled dough from the fridge and roll it out on a lightly floured surface to a thickness of ½ cm ( ¼ inch) using a rolling pin.
Cut 50 circles from the dough using a 7cm (3 inches) round cookie cutter and place the cookies onto the prepared baking sheet pans. Use a smaller cookie cutter to cut hearts or circles into half of the cookies.
Bake the cookies in a preheated oven for 15 minutes or until the cookies are light golden brown. Allow the cookies to cool on a cooling rack.
Spread a teaspoon of jam over the cookies that will form the cookie base. Place the top cookie onto this and then dust the top of the cookie sandwiches with icing sugar. Serve, and enjoy!