Preheat oven to 325°.
Place 1/4 cup hazelnuts, 1 tablespoon brown sugar, and chocolate wafers in a food processor; process until finely ground. Add oil; process until crumbs are moist. Firmly press crumb mixture into bottom of a 9-inch springform pan coated with cooking spray. Wrap outside of pan with a double layer of aluminum foil.
Combine instant coffee granules and 1 tablespoon hot water in a small bowl. Place cheeses in food processor; process until smooth. Add coffee mixture, cocoa, and next 6 ingredients (cocoa through salt); process until well blended. Add eggs; process until smooth. Pour mixture into pan.
Place pan in a large baking pan; add hot water to baking pan to a depth of 1 inch. Bake at 325° for 1 hour or until cheesecake center barely moves when pan is touched.
Remove cheesecake from oven; run a knife around outside edge. Cool to room temperature. Cover and chill at least 8 hours. Remove cheesecake from springform pan; sprinkle with 1/4 cup hazelnuts.