Preheat oven to 350°; Grease a 9-inch springform pan; set aside.
Crust-In a food processor, pulse crumbs, sugar, espresso powder, and cinnamon until fine.
Pour butter through feed tube and pulse until combined; press into prepared pan and freeze.
Filling-in a saucepan, heat 2 t milk, espresso powder, and butter until butter melts; set aside.
In a large bowl, beat Neufchatel cheese, cream cheese, and sugar on med-high speed for 3 minutes.
Add eggs, one at a time, beating after each addition.
Decrease speed to low, add milk, hazelnuts, liqueur, and espresso mixture.
Pour over frozen crust.
Bake for 45-55 minutes or until the top is light brown; cool for 2 hours; cover and refrigerate for 6 hours before decorating.
Syrup- In a saucepan, bring sugar and water to a boil, about 5-8 minutes or until sugar is dissolved (make sure you heat sugar and water to a full boil and cook until sugar is dissolved or the sugar may crystallize).
Remove from heat and add liqueur; cool.
Syrup will keep in a covered container in a refrigerator for up to 2 weeks.
To serve-slide a slice on a plate; pour 2 T syrup on top and sprinkle with hazelnuts.