Lightly grease a 2-quart shallow baking dish; set aside. In a very large bowl, combine half-and-half, pumpkin, brown sugar, eggs, vanilla, pumpkin pie spice, and cinnamon. Add bread pieces; stir to moisten evenly. Stir in raisins. Transfer mixture to the prepared baking dish. Cover and chill for 1 to 4 hours.
Meanwhile, for sauce:
In a small saucepan, combine granulated sugar, evaporated milk, butter, and corn syrup. Bring to boiling; reduce heat. Boil gently, uncovered, for 1 minute. Cool to room temperature. Transfer to a serving bowl. Stir in toffee pieces.
Preheat oven to 350 degrees F. Bake bread pudding, uncovered, about 35 minutes or until a knife inserted in the center comes out clean. Cool on a wire rack for 30 minutes. Serve warm bread pudding with sauce. Makes 8 servings.