At their heart, financiers are simple, stir-together mini cakes. Cakelettes if you will. Since these cakes are so simple to make, this version provides a lesson on adding flavor through toasting the nuts and the butter. The result: a harmonious little treat that becomes more than a sum of its parts. They're toasty, nutty, almost caramelized, with a mellow coffee flavor. (Even the kids loved these cakes.) Whenever baking with nuts, toast them. Raw nuts have almost no flavor compared with toasted nuts. But you don’t just toast the nuts. Most financier recipes begin with browning butter to a dark toasty color. Just like with the nuts, you know it's ready by the smell. Even if you don't think you like coffee-flavored things, give this a taste. The coffee works in concert with the other flavors and provides a rich, subtle bass note. Use a medium to light-roast coffee if you have it—those give less bitterness than a dark roast.