Heat the oven to 200C/180C Fan. Melt the butter in a frying pan and gently cook the shallots, with the lid on for 10 minutes. Add the sugar and vinegar and turn up the heat. Cook stirring occasionally for 5 minutes so that the shallots caramelised. Set aside to cool.
In a large bowl combine the flour, salt and baking powder then stir in 50g of the cheese and the shallots.
Make a well in the centre of the flour and pour in the buttermilk. Splay your fingers out like a big fork and mix gently but quickly to combine to a dough. To get the lightest bread, minimise the amount you handle the dough.
Turn the dough out onto a floured surface and pat into a circle. Transfer to a non-stick baking sheet and pat down a little. Scatter with the remaining cheese and cut a large cross, deep into the dough and bake for 40-45 mins until the bottom sounds hollow when tapped.
While the bread is baking, beat the butter in a bowl until soft then beat in the herbs. Lay out a sheet of clingfilm on the surface and spoon the butter into a line near the bottom of the cling film, fold the cling film over the butter and shape it into a sausage. Roll the butter up in the cling film and twist the ends to make it tight. Pop it the fridge and when you’re ready to serve the bread, cut disks of butter to spread on the warm slices.
Note: Soda bread is a dense bread, this one is perfect for serving with cheese or dipping in soup. If you don’t finish the butter, slice into disks and keep it in the freezer, use it on pasta, fish, baked potatoes etc.