In a food processor, combine crumbled blue cheese and butter; process until creamy.
Mix flour, cornstarch, salt, and pepper together in a small bowl. Add to blue cheese mixture, pulsing just to combine (until mixture resembles coarse meal). Add hazelnuts and process just until moist clumps form.
Transfer dough to a sheet of plastic wrap and work with your palm until dough holds together. Shape dough into a log (depending on the shape of shortbread you want, shape either into a round, square, or rectangular log). Wrap in plastic wrap and refrigerate at least one hour, but may be refrigerated long.
Preheat oven to 325 degrees F. Line baking sheet with parchment paper or a silpad. When ready to bake, slice approximately 1/4-inch thick and bake the shortbreads on prepared baking sheet. Bake on center oven rack let cool on racks.
NOTE: The shortbread can be prepared up to 3 days in advance and stored in airtight containers at room temperature.
When ready to serve, either serve plain or spread approximately 1/4 teaspoon cream cheese on top of each shortbread.
Makes 30 to 35 shortbreads.
* Toasted Hazelnuts: Preheat oven to 275 degrees F. Place shelled hazelnuts on a non-greased cookie sheet only one layer high. Place in oven for 20 to 30 minutes until the skins crack and the nut meat turn a light golden color. To remove more of the skin, pour the hot nuts onto a clean terry-cloth towel and wrap it closed. Let the nuts steam for 4 to 5 minutes then rub vigorously for 1 to 3 minutes. Rub longer to remove more skin.
Blue Cheese and Hazelnut Shortbread Recipe: https://whatscookingamerica.net/appetizers/bluecheeseshortbread.htm