Pistachio Brown Butter Financiers

Steps

1. Preheat the oven to 375°F with a rack in the center. Generously butter a 12-cup mini muffin tin (or a financier mold), making sure to coat the rims so the cakes release cleanly.
2. Brown the butter: Melt the butter in a small light-colored saucepan over medium heat, swirling occasionally. Once the foam subsides, keep cooking until the milk solids turn golden-brown and the butter smells nutty, 5 to 7 minutes — watch closely so it doesn't scorch. Pour into a heatproof bowl, scraping in all the browned bits, and let cool until just warm, about 15 minutes.
3. Meanwhile, toast the pistachios: Spread the ½ cup pistachios on a small baking sheet and toast in the oven until fragrant and lightly golden, 6 to 8 minutes. Let cool completely, then pulse in a food processor until finely ground into a coarse flour. Finely chop the remaining 3 tablespoons for the topping.
4. In a large bowl, whisk together the ground pistachios, almond flour, powdered sugar, all-purpose flour, and salt.
5. Add the egg whites, vanilla, almond extract (if using), and honey (if using) to the dry ingredients and stir with a rubber spatula until a smooth, thick batter forms. Pour in the cooled brown butter and stir until fully incorporated and glossy.
6. Divide the batter evenly among the prepared cups, filling each about three-quarters full. Scatter the chopped pistachios over the tops.
7. Bake for 14 to 16 minutes, until the financiers are golden and domed and the edges are deeply browned. A toothpick inserted in the center should come out with a few moist crumbs. Cool in the pan for 5 minutes, then turn out onto a wire rack to cool completely. Dust with powdered sugar just before serving.