This is a recipe for authentic financiers that can be made in 30 minutes, perfect for using up egg whites. Since there's no need to let the dough rest, you can make them whenever the mood strikes you. The outside is crisp and fragrant, the inside is moist, and the rich aroma of butter fills your mouth. The secret to its deliciousness lies in how you make the browned butter; if you follow the key points, you can achieve a taste like those from a bakery. It's also recommended as a Valentine's Day gift or souvenir. It's delicious fresh out of the oven, but the next day it becomes even more moist, offering a different kind of deliciousness.