Preheat oven to 350 degrees Fahrenheit.

Place hazelnuts in a 9×13-inch baking pan. Bake for 12–15 minutes, until fragrant and lightly browned.

Transfer to a clean dishtowel; rub to remove skins. It’s okay if some skin remains.

Place hazelnuts in a food processor fitted with S-blade. Process until coarsely chopped.

Set aside 1/2 cup + three tablespoons chopped hazelnuts.

Continue to process remaining hazelnuts at high speed until pasty, scraping down sides a few times in middle.

Add chocolate chips and eggs to food processor. Process at high speed until chocolate chips have been finely ground.

Meanwhile, in a heavy saucepan, heat parve milk and brandy, if using, until scalded (hot but not boiling).

As food processor runs at a low speed, drizzle hot milk mixture through food processor chute in a very slow stream.

Transfer mixture back to saucepan.

Cook over low heat, stirring constantly with a wooden spoon for 10 minutes, until mixture reaches 160 degrees Fahrenheit or begins to thicken like a custard.

Immediately plunge saucepan in a bowl of ice water. This brings eggs to a safe eating temperature.

Remove from heat.

Stir in 1/2 cup reserved chopped hazelnuts.

Spoon into mini mousse cups.

Top with remaining three tablespoons chopped hazelnuts.

Refrigerate until cool before serving.