I adore all things pumpkin, as well as all things fudge. The two together is like something created by a chef version of Einstein.
Fudge can be a little tricky (I've had mine come out like runny ice cream topping and like brittle candy), but there are a number of tricks to help ease the process. First, test the boiling point of your thermometer in a pot of water. The thermometer should read 212 degrees when the water is boiling. Otherwise, you'll need to adjust all thermometer readings by however much the reading is off by. Also, cook the fudge in a high quality dutch oven with a really heavy, solid base. I use my Le Creuset oven. If you use a thin aluminum pan, the bottom of the fudge will burn.
6 cups sugar
2 cups milk
6 tablespoons light corn syrup
1 cup pumpkin puree
1/2 teaspoon salt
4 teaspoons pumpkin pie spice
3 teaspoons vanilla
1 cup butter
1) Grease two 9×13 inch pans.
2) In a large, heavy pan, mix sugar, milk, corn syrup, pumpkin and salt. Cook over high heat, stirring constantly, until it reaches a boil. Reduce heat to medium and continue boiling (without stirring) until the mixture reaches 232 degrees Fahrenheit.
3) Remove pan from heat and place the bottom of the pan in a cold bath (I usually just fill up the bottom of my sink with cold water for this). Add the pumpkin pie spice, vanilla and butter but don't stir yet. Cool to 110 degrees Fahrenheit.
4) Beat extremely well with a hand mixer until the mixture becomes thick and loses its glossiness. Do not beat past the point when it is no longer glossy. Quickly pour into the greased pans and let sit several hours before cutting.
If the mixture fails to solidify, you may want to and add a package of butterscotch morsels and reheat it to 212 degrees before cooling and mixing again. This often helps stubborn fudge firm up. Otherwise, enjoy it as an ice cream topper!