Pre-heat the oven to 220ºC/200ºC fan.
Line a baking tray with a sheet of baking parchment or non-stick baking sheet.
Put all of the dry ingredients into a large bowl (400g flour, 1 tsp bicarbonate of soda, 1 tsp salt) and give them a quick stir so they’re all mixed up.
Add in the buttermilk (300ml) and mix thoroughly until you have a ball of dough. You can use a spoon but I prefer to use my hands as its easier to ensure that everything is fully combined. If there are any dry bits at the bottom that won’t combine add a little extra buttermilk if you have it or if you don’t a little milk until it is all combined.
Form the dough into two balls and place them onto the baking tray. Using a sharp knife cut a cross shape in the top, cutting through to about halfway down the loaf.
Bake the loaves in the oven for 25 minutes, remove them from the oven, loosely cover them with foil and then return them to the oven for a further 10 minutes.
Check the loaves are cooked by tapping them on the bottom. They should sound hollow. If they don’t then pop them back in (still covered in foil) for another few minutes.
Once cooked, move to a rack to cool.