In a large bowl, mix together flour, baking powder and salt. If using sugar, add it here too.

Measure out butter and cut into small pieces. Add to the flour in bowl.

Use fingers to squish butter into the flour, until it forms about pea-size chunks (the chunks are important!).

Add milk and lightly mix in until the dough just begins to come together. You want the chunks of butter to stay together for the most part.

Remove dough from bowl and form into a fat rectangle. Wrap in plastic and refrigerate for at least one hour.

After chilled, unwrap dough and dust with flour. Roll out to about 3 times the size. If it starts to stick just dust with a little more flour.

Fold dough in three and roll out again.

After rolling out the second time, fold in three again, re-wrap with plastic and chill in fridge for another hour.

Remove from refrigerator and repeat the roll-out, fold, roll-out, fold process. You can now roll them out to cut and bake OR if you want even MORE flaky layers, refrigerate for an additional hour, then roll-fold, roll-fold one last time.

After your last rolling and folding, you can roll out to cut. Roll dough out so it's 1/2 inch or 12mm thick. Cut into 4-6 squares with a knife, or cut out rounds with the rime of a glass, etc. (I made a little extra so the pictures shows more)

Have your oven preheated to 400°F/200°C. Bake for 20-30 minutes until tops are golden brown. (Mine only took 20 minutes so keep an eye on them!)