Whisk together the cornstarch, sugar and salt in a saucepan until smooth. Add the milk and half-and-half and stir to combine. Bring the ingredients to a simmer over medium heat whisking constantly. Cook until the mixture begins to thicken. Remove the pan from heat and stir in the vanilla, butter cinnamon and cayenne. Pour the pudding into 4 small serving bowls and chill for 1 hour before serving.