Step 1Heat the oven to 325 degrees. Measure one-fourth cup of pine nuts into a food processor. Pulse until coarsely ground. Break up the almond paste and add it to the food processor. Process just until mixed.
Step 2Add the sugar through the tube while the processor is running and process until the mixture resembles coarse crumbs.
Step 3Add the egg whites and vanilla through the tube while the processor is running. Process until smooth. Add the flour and salt and process just until blended.
Step 4Place the remaining pine nuts in a small bowl. Using a teaspoon and lightly moistened hands, drop the dough by rounded teaspoons into pine nuts. Roll the cookies in the pine nuts to coat.
Step 5Place the cookies 2 inches apart on parchment-lined cookie sheets. Bake until lightly browned, about 20 to 22 minutes.
Step 6Cool slightly. Dust with powdered sugar.
Step 7Remove the cookies from the parchment paper. Store them in an airtight container.