Sift flour and salt into a mixing bowl. Cut and rub in 30g butter from the 225g stick of butter. Bind flour mixture with the iced water and lemon juice. Mix well and knead till smooth. Rest for 15 minutes.
Place the remaining butter between two sheets of grease-proof paper. Roll out flat to a square. Refrigerate.
Place dough on a lightly floured surface. Roll to a square large enough to enclose the butter. Dust both sides of butter with flour, before wrapping with the square dough like a parcel.
Roll out dough into an oblong shape. Fold into a three-layered rectangle by turning bottom third up and top third down. Seal the edges and chill.
Repeat rolling and folding and deep-freezing it for 15 minutes. Repeat process one more time (process should be done three times altogether).
Roll final pastry to 1/2cm thickness, cut to desired sizes and deep-freeze in an airtight container till required.