2 cups flour
1/3 cup packed light brown sugar
1/3 cup powdered sugar
1 tbsp. plus 1 tsp. instant coffee or espresso powder
1/2 tsp. salt
1 cup (2 sticks) chilled salted butter, cut into 1/2-inch pieces (allow to sit at room temperature for 15 minutes)
1 tsp. vanilla extract
1 cup hazelnuts, toasted and coarsely chopped
2 ounces semisweet chocolate, chopped
1. Preheat oven to 350º.
2. Blend flour, sugars, 1 tbsp. espresso powder and salt in food processor. Add butter, vanilla and 2/3 cup hazelnuts. Using pulse button, process until mixture resembles coarse meal. Transfer dough to lightly floured work surface. Knead just until dough comes together. Divide dough in half.
3. Press each half into 9-inch tart (or cake) pans that have been coated with nonstick cooking spray. Prick dough with fork several times. Bake until deep golden brown, 25 to 30 minutes. Transfer shortbread to rack; cool 5 minutes. Remove shortbread from pan by inverting shortbread onto plates slightly smaller than pan and re-inverting onto cutting board. Cut into 24 wedges; cool completely.
4. Mix 2 tbsp. hot water and remaining 1 tsp. espresso powder in small saucepan. Add chocolate. Stir over low heat until chocolate is smooth. Remove from heat. Drizzle melted chocolate over shortbread wedges; sprinkle with remaining hazelnuts. Let stand until chocolate sets. Store in airtight container. Freezes well. Yield: 2 dozen.