Grind the oatmeal finely and set aside.
Steep the hojicha tea bag in hot water and let it cool.
In a bowl, combine the ground oatmeal and baking powder.
In another bowl, mix together the eggs, olive oil, milk, brewed hojicha tea, and sugar until well combined.
Combine the dry ingredients with the wet ingredients to form a batter.
Pour the batter into a pound cake mold.
Bake in the oven at 180°C (356°F) for 35-40 minutes.
Once cooled, slice the finished pound cake.