Instructions

1. Cut the butter into cubes and let it soften at room temperature for 10 minutes.
   
2. Place the butter in a deep bowl, add the sugar and egg, and beat with a mixer for 2-3 minutes.
   
3. Add the flour, a pinch of salt, and the lemon zest. Mix with a spoon, then knead with your hands until you get a smooth, homogeneous dough.
   
4. Form the dough into a ball, wrap it in plastic wrap, and let it rest in the refrigerator for at least 30 minutes.
   
5. Then divide the dough into two parts, one 1/3 and one 2/3 of the dough. Wrap the smaller portion in plastic wrap and return it to the refrigerator.
   
6. Flour the tart pan.
   
7. Roll out the larger portion of the dough into a circle that is a couple of centimeters (about 1 inch) larger than the bottom of the tart pan. Place the dough in the pan and press it in, covering the bottom and sides. Prick the bottom with a fork.
   
8. Preheat the oven to 180°C/350°F (160°C/320°F for a ventilated oven).
   
9. Spread the jam evenly over the dough.
   
10. Take the remaining dough from the refrigerator. Roll it out and cut it into strips 1-2 cm (around 1/2 inch) wide. Arrange the strips in a lattice pattern over the jam, trimming any excess. Seal the edges.
    
11. Bake the crostata in the preheated oven for 30-40 minutes (25-35 minutes in a ventilated oven) until golden brown.