In a large, greased bowl, combine the first four ingredients; set aside.

In a large saucepan, combine sugar, butter, corn syrup and water. Cook over medium heat, stirring occasionally, until a candy thermometer reads 280F to 290F (soft-crack stage). Remove from the heat; stir in cinnamon. Pour over popcorn mixture; stir until evenly coated.

Immediately pour into a greased 15 x 19 x 1-inch pan. When cool enough to handle, break into pieces. Store in an airtight container.