This hazelnut and orange cake is a delicious and refreshing dessert that is perfect for any occasion. The nutty taste of hazelnuts is complemented by the tangy flavor of orange, making this cake a unique and flavorful treat. To make this cake, you will need hazelnut flour, eggs, sugar, butter, orange zest, orange juice, and baking powder. Mix all the ingredients together, pour the batter into a cake pan, and bake for 30-35 minutes. Once the cake is cooled, you can top it with whipped cream or an orange glaze for an extra burst of flavor.