Heat the oven to gas 6, 200°C, fan 180°C. Lightly oil a baking tray approximately 20 x 30cm and line with nonstick baking paper. Sieve the flour and baking powder into a mixing bowl and make a well in the centre. Add the buttermilk, salt and dried herbs. Using a knife, bring the mixture together to form soft dough. Alternatively, use a low speed on an electric mixer. Turn the dough out onto a floured surface and knead lightly until smooth. Roll out to a rough 30cm square. Spread the tomato purée over the surface of the dough and scatter with the cheese. Chop the ham and pineapple into small pieces and scatter on top of the cheese. Roll the dough to form a large sausage shape and slice into 10 pieces. Place on the prepared baking tray, cut-side up, and bake in the oven for 25-30 minutes, or until golden. Remove from the oven; cool slightly, then remove the twirls from the tin. Cut or tear off the individual twirls to eat. For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.