Scoops of chocolate and coffee ice cream get ladled with chocolate and marshmallow sauces, then topped with toasted hazelnuts and chunks of chocolate in this Rocky Road-inspired sundae that's smooth sailing.
Preheat oven to 350 degrees. Place hazelnuts in a single layer on a rimmed baking sheet; toast until skins begin to split, about 10 minutes. Rub warm nuts with a clean kitchen towel to remove skins. Return them to tray; toast until fragrant and golden brown, 10 minutes more. Let cool.
Place 2 scoops chocolate ice cream and 1 scoop coffee ice cream in each of four bowls. Top with chocolate and marshmallow sauces. Sprinkle with hazelnuts and chocolate chunks; serve.