Begin by preheating your oven to 220°C (200°C fan) and lining a baking tray with parchment paper.
In a mixing bowl, blend together all-purpose flour, baking powder, baking soda, and salt.
Add the cold, diced butter into the dry ingredients and use your fingertips to work it in until the mixture reaches a breadcrumb-like consistency.
Add the buttermilk and gently stir until just combined, taking care not to overmix; the dough should have a slightly sticky texture.
Turn the dough out onto a lightly floured surface and lightly knead it a few times until it forms a cohesive mass.
Roll out the dough to a thickness of approximately 2cm and employ a round cutter to shape the biscuits.
Arrange the biscuits on the prepared baking tray and bake them in the preheated oven for 12-15 minutes or until they turn a golden brown colour and are thoroughly cooked.
Take them out of the oven and allow them to cool for a few minutes before serving.