Soak the oats by pouring boiling water over the Irish oatmeal in a large bowl and let soak for 1 to 4 hours.

Prepare the dry ingredients by mixing all-purpose flour, baking powder, and salt in a separate bowl.

Mix the wet ingredients by whisking the egg and milk together until combined.

Preheat the oven to 350°F (175°C) and grease a 9x5-inch loaf pan.

Combine wet ingredients with oats by stirring melted butter and honey into the oat mixture.

Mix everything together gradually adding the egg and milk mixture and dry ingredients until just combined.

Fold in chopped dates and hazelnuts carefully.

Pour the batter into the prepared loaf pan and bake for 1 hour and 10 minutes.

Cool the bread in the pan for 10 minutes, then transfer to a wire rack.

Prepare whipped butter by beating together butter and a splash of milk until fluffy.