Beat 1/4 cup oil, 1/4 cup sugar, and egg in a large mixing bowl at medium speed with an electric mixer until blended.
Combine flour and next 3 ingredients; add to sugar mixture alternately with whipping cream, beginning and ending with flour mixture. Beat at low speed until blended after each addition.
Pour remaining 3 cups oil into a heavy saucepan; heat to 325° to 350°.
Drop dough by tablespoonfuls into hot oil, and fry, in batches, 4 to 5 minutes or until golden. Remove with a slotted spoon; drain on paper towels.
Stir together remaining 1/4 cup sugar and cinnamon; sprinkle evenly over puffs.