Double Pecan Thumbprints

Name: Double Pecan Thumbprints
Ingredients: 2 cups pecan halves; 1/3 cup granulated sugar; 1 large egg white; 2 Tbsp. unsalted butter, room temperature; 2 tsp. espresso powder; 1/2 tsp. kosher salt; 1/4 tsp. almond extract; 1 1/4 cups all-purpose flour; 1 tsp. kosher salt; 1/2 tsp. baking powder; 3/4 cup (1 1/2 sticks) unsalted butter, room temperature; 1/4 cup granulated sugar; 3/4 cup powdered sugar, divided; plus more for serving (optional); 1 large egg yolk; 1 tsp. vanilla extract or paste