In a bowl sift flour and baking pownder; add sugar and butter, rub with finger until you have a sand dough.
Add egg, zest from the lemon, and milk ( you could need some less or some more, it depends on the size of the egg) and knead just until well combined.
Put the dough on a baking tray covered with baking paper, give it the shape of a rectangle.
Spread mustard or jam on the dough then bend the long sides of the rectangle overlapping them.
Sprinkle sugar grain on top of the pinza.
Bake at 338°F for 30/ 40 minutes.
Let it cool completely before serving; it’s ok if the cake crumbles a little.
Recipe Notes
It can be stored in an airtight box for a long time.