Irish soda bread is made with baking soda rather than yeast!
Preheat oven to 350° F.
Mix together both flours, baking soda, baking powder and salt.
In a blender, blend 1 cup buttermilk and spinach. Set aside.
In a stand mixer, add the sugar, ½ cup butter and egg and blend well. Mix in the dry ingredients and then add the buttermilk/spinach mixture until just combined. Using a dough hook, kneed for a few minutes. If you do not have a stand mixer, mix in a bowl and kneed by hand on a floured board.
Whisk together the ¼ cup buttermilk and melted butter.
Split dough in half and mold into two rounds. Using a knife, cut a large X on the tops of each bread and brush with the buttermilk and melted butter. Sprinkle the tops with oatmeal and bake for 40-50 minutes, checking after 30. You can brush with additional buttermilk and butter while baking after 20 minutes. Breads are done when a knife inserted into the middle comes out clean.
Once done, wrap in towel until ready to eat. Serve with butter.