Although financières are typically baked in small, rectangular molds to resemble gold bars, we used a mini muffin pan for ours to create these petits gâteaux that are laden with finely chopped pistachios and are perfect for teatime.

1. Spray 2 (24-well) miniature muffin pans with baking spray with flour. 
2. In a medium saucepan, melt butter over medium heat. Cook, stirring occasionally, until butter turns golden brown and has a nutty aroma. Let cool completely. 
3. In a large bowl, whisk together granulated sugar, brown sugar, egg whites, orange zest, and salt until smooth. In a medium bowl, whisk together flour, ground pistachios, and baking powder. Stir flour mixture into egg white mixture. Add cooled browned butter, and stir until smooth. Refrigerate for 1 hour. 
4. Using a levered 2-teaspoon scoop, divide batter among wells of prepared muffin pans. Sprinkle with chopped pistachios. 
5. Bake until edges of financières are golden brown and a wooden pick inserted in centers comes out clean, approximately 10 minutes. Let cool in pans for 5 minutes. Turn out financiers onto wire racks, and let cool completely.  Store at room temperature in airtight containers with layers separated with wax paper.
6. Just before serving, place Sweetened Whipped Cream in a piping bag fitted with a large open-star tip (Wilton #1M). Pipe a dollop of Sweetened Whipped Cream onto each financière. 
7. Garnish with a sprinkle of pistachios, if desired.