Heat the oven to 400 F and make sure the oven rack is in the center position. Prepare a baking sheet by covering it with parchment paper. You can also grease or use parchment on the bottom of a 8-10" cast iron skillet, a cake pan, or use a 5 quart round Dutch oven (no lid).

In a large bowl mix the gluten-free flour, salt, baking soda, and sugar until it's well combined.

Add in the cold butter cubes by cutting it in with a pastry cutter or a fork.

In a small bowl combine the beaten egg and the buttermilk. Pour the buttermilk mixture into the flour mixture all at once and stir it with a fork until the liquid is absorbed and the bread dough starts to hold together like a rough biscuit dough. The dough will be wet but if it's too sticky, mix in a tiny bit more flour. Stir in the raisins if you're using them.

Lightly sprinkle some of the gf flour on a cutting board. Using your hands, pick up the dough and form it into a round dome shape loaf that's about 8-9" in diameter on the cutting board. Transfer the dough to the prepared baking sheet or pan.

With a sharp knife, make a deep ¾" X shape into the loaf.

Bake the Irish soda bread for about 45-50 minutes or until the bread is golden brown a cake tester or wooden skewer comes out clean. If the bread seems to be browning too fast during cooking, you can add foil over the top.

Remove the bread from the oven and let it cool on a wire rack. Serve warm or at room temp with butter and/or jam. Yum!