Whisk together sugar, pumpkin puree, cocoa powder, pumpkin pie spice and ½ cup milk in a medium saucepan over medium-low heat until combined.

Add the remaining milk and heat over medium heat, whisking occasionally, until the mixture just begins to bubble but does not boil.

Then, turn off the heat and add the chocolate and vanilla and whisk until the chocolate is melted and the mixture is smooth.

Pour into 4 to 6 small mugs and serve with homemade whipped cream.