An attractive and tasty bar cookie adapted from Family Circle magazine. Using the Nutella as frosting makes this simple and quick to put together. Note added 9/16/05: Even though the recipe calls simply for an egg yolk, I would suggest using the whole egg as I believe they will hold together better. Thanks to Caroline Cooks for testing this change. :)
- Heat oven to 350°F and generously coat a 13x9-inch baking pan with nonstick cooking spray (I lined with non-stick aluminum foil, allowing excess over sides of pan so I can lift them out to cut).
- Beat together butter, sugar, egg yolk and vanilla in medium-size bowl until well blended.
- Mix in flour, salt and 1/3 cup finely chopped hazelnuts.
- Press evenly in prepared pan.
- Bake for 20 minutes or until top is golden brown.
- Remove pan to wire rack and cool 10 minutes.
- Spread top evenly with chocolate-hazelnut spread, then sprinkle with remaining hazelnuts.
- Chill to set top, then cut into 24 bars.