To make the crust, pour the flour into a mixing bowl. Work the butter in with your fingers or with a paddle attachment until it resembles coarse sand. Add water and mix it together until it forms a ball of dough when pressed together. Wrap with plastic wrap and refrigerate for 30 minutes until firm.

Preheat your oven to 400F. Lightly grease a 9" tin pan with butter. Set aside.

Set aside 5 1/2 oz of the dough in the refrigerator. Take the rest of the dough and roll it out into a circle, around 11". Carefully place the circle into the prepared pan and press it gently into edges. Prick the center of the pastry with a fork to prevent it from puffing up while it's baking. Trim the edges with a knife so that you will only have a 1/2" overhang. Place this into the refrigerator.

Take the remaining pastry and roll it out on a sheet of parchment. Brush with egg wash and refrigerate until needed.

In a saucepan over medium low heat, add the golden syrup. Heat just until warm. Stir in the breadcrumbs, lemon juice and zest. Pour the mixture into the prepared pan and spread evenly.

Cut 1/2" strips out of the reserved rolled out dough. Start making a woven lattice on top. Trim off any excess and gently press the edges to the edge of the pan. Edge wash the edges.

Bake for 25-30 minutes until golden brown and the filling has set. Remove the tart from the pan and serve warm or cold.