Whisk the egg and buttermilk. Set aside ¼ of the liquid.
In a big bowl mix the whole wheat flour and the all-purpose flour, salt and baking soda.
Add the chilled butter and rub in the flour till the flour resembles breadcrumbs.
Make a well in the of the flour and add the ¾ liquid. Mix to get a soft dough that is not sticky. Add more liquid as needed from the balance ¼ cup.
Turn the dough on a lightly floured surface and make a ball about 8 inches by 8 inches and 1.5 inches thick. Place on a well dusted baking tray.
Score the bread in the form of a cross and make some dimples at the end of each line of the cross.
Glaze with the leftover buttermilk and egg mixture.
Sprinkle the oats, if using on top.
Transfer to the oven and bake for 15 minutes at 215C then lower the temperature and bake for 30 minutes at 200C.
Your bread is ready when it is brown on top and sounds hollow when knocked on.
How to serve:
To serve the Irish soda bread, slice it when warm and serve with butter, and/or jam.
How about some of the Soda bread with soup or stew? Tastes great!
Notes
Protips:
Take a large bowl, basin to mix the dough. This prevents over-mixing the dough and keeps the bread soft.
When adding the baking soda, break the lumps before you measure and level the spoon.
Excess baking soda makes the bread taste bad. So take care.
Do not avoid the buttermilk in this recipe. The baking soda and lactic acid in the buttermilk react. This helps the bread to rise and you cannot taste it in the bread.
In India, we have easy access to buttermilk but in case you do not add 2 tablespoon vinegar or lemon juice to 1 cup of milk. Mix and let it sit for about 30 minutes. Your buttermilk is ready.
Do not be tempted to open the oven door if you want a crust, crisp crust. I know this is the most difficult part. I love to peek at my bakes.