How to Make It
In a saucepan, heat the cream with the granulated sugar until hot to the touch. In a bowl, whisk the egg yolks. Gradually whisk in 1 cup of the hot cream. Scrape the mixture into the saucepan and cook over moderate heat, whisking, until slightly thickened, 3 minutes. Remove from the heat. Add the chocolate and let stand until melted, 5 minutes. Whisk until smooth. Transfer to a shallow bowl and refrigerate until very cold, at least 4 hours.
In a bowl, beat the cream with the confectioners' sugar, espresso and vanilla until firm. Spoon the cream into ten 1/2-cup ramekins and freeze until firm.
Preheat the oven to 350°. Butter the bread on both sides. Toast on a baking sheet for about 8 minutes, or until golden.
Spoon the milk-chocolate cremoso onto plates, sprinkle with the hazelnuts and drizzle lightly with olive oil. Serve the espresso parfait and toast on the side.