Combine the milk, sugar, scraped Rodelle Vanilla Bean, and spices in a large, heavy-bottomed saucepan. The more surface area, the faster the milk will reduce, so use a large saucepan or even a soup pot if you like. The heavier the pot, the less likely the milk is to scorch.
Bring the milk to a simmer over medium heat, stirring very frequently, scraping the bottom and sides of the pot to prevent the milk from burning.
When the milk has reached a simmer, reduce the heat to low and continue to cook, stirring frequently, until the mixture has reduced to between 2 1/4 and 2 1/2 cups. You can speed the process up to about half an hour by keeping the heat at medium and stirring constantly, or you can reduce the heat to very low and give it a stir every few minutes, which will make the process take a couple of hours.
When the milk has reduced (pour it into a heatproof measuring pitcher to find out), stir in the cream, pumpkin puree and salt.
Continue to heat the mixture until steaming, stirring occasionally, then remove from the heat, cover, and steep for 10 minutes.
Strain the milk mixture through a fine mesh sieve and let cool slightly for 10-15 minutes, stirring occasionally to release the heat (this prevents the alcohol from curdling the mixture when you add it). Optionally whip the mixture with an immersion blender (this helps prevent the fat from the dairy from clumping up in the fridge).
When the mixture has cooled, stir in the alcohol.
This liqueur is not shelf-stable, so pour it into jars or bottles and store in the fridge. It should keep for at least a month.
