2 cups coffee ice cream chocolate syrup, as needed
Preheat oven to 375°F.
Mix hazelnuts, flour, oats and salt in a medium bowl; set aside.
Heat sugar, butter, corn syrup and milk in a saucepan over medium-high heat, stirring constantly, until mixture comes to a boil. Remove from heat and pour into hazelnut mixture. Add vanilla and stir until blended. Cool for 30 minutes.
Place mounded teaspoons of dough 3" apart, onto parchment-lined baking sheet, Flatten dough to1⁄2"thick and round edges with fingertips.
Bake for 6-9 minutes until edges are golden. Cool 10 minutes and remove from pan.
To serve: Drizzle dessert plates with chocolate syrup, if desired. Place one cookie on each plate. Top with 1/4 cup scoop of ice cream and top with another cookie. Serve immediately.