Lemon Shortbread Star Cookies
For the dough: Mix the flour, lemon zest, sugar and a pinch of salt in a large bowl. Make a well in the center, add the beaten egg and distribute the butter over the top. Mix with hands to form a smooth dough, wrap with plastic wrap and refrigerate for 30 minutes.
Preheat the oven to 180°C (approximately 350°F). Line a baking sheet with parchment paper.
Transfer the dough to a floured surface and roll out to about 0.4 cm (approximately 1/8 inch) thick. Cut into stars about 3.5 cm (approximately 1 1/4 inch) wide using a cookie cutter. Place on the prepared baking sheet and bake for 10 minutes, until golden brown. Remove from the oven and cool on a wire rack.
Whisk together the powdered sugar and lemon juice until smooth. Spread onto half of the stars and allow to dry.
Warm the lemon jelly in the microwave and spread onto the remaining cookies. Allow to dry. Store the cookies in an airtight container.