It's like everyone's favorite spread hazelnut-chocolate spread, but in a rich, creamy ice cream. You're welcome.
Spray a 9 by 4 1/2 by 2 3/4-inch loaf pan with cooking spray. Line pan with plastic wrap, overlapping edges; set aside. Coarsely chop 1 cup hazelnuts; combine with milk in medium saucepan. Bring to a gentle boil. Remove from heat; steep for 1 hour.
Combine egg yolks and sugar in bowl of electric mixer. Using whip attachment, beat at medium-high speed until very thick and pale yellow, 2 to 3 minutes. Meanwhile, strain milk, and discard nuts. Bring milk back to a simmer.
Whisk half of the hot milk into the sugar mixture. Return to saucepan. Cook over low heat, stirring, until thick enough to coat a wooden spoon, 6 to 8 minutes.
Remove from heat. Stir in cream; pass through fine strainer. Pour into medium bowl; chill over ice bath. Stir in Frangelico. Freeze in ice-cream maker according to manufacturer's instructions. Cut remaining hazelnuts in half; add nuts to ice cream, churning to incorporate, about 30 seconds.
Spoon one-third of ice cream into prepared pan; drizzle with 1/3 cup gianduja. Repeat layering process with ice cream and gianduja, ending with an ice-cream layer. Cover with overlapping plastic wrap; freeze until firm.
To serve, invert loaf pan onto serving plate. Cover bottom and sides of pan with cold wet towel; rub for about 1 minute. Pull plastic wrap down; ice cream will slide from pan. Remove plastic wrap, slice, and serve.