Line an 11- x 7-inch glass or ceramic baking dish with foil; coat with cooking spray. Combine sugar, pumpkin, milk, and syrup in a saucepan over medium; cook 30 minutes or until a candy thermometer registers 237°F, stirring constantly. Stir in butter, salt, spice, cream cheese, and chocolate, cooking until melted (mixture will be very thick). Coat a spatula with cooking spray; spoon mixture into prepared dish, smoothing into an even layer. Cool completely at room temperature, 1 1/2 to 2 hours. Cut into 32 squares.