In a bowl, mix together the milk, pumpkin, egg, oil and vinegar.

In a separate bowl, combine the flour, brown sugar, baking powder, baking soda, allspice, cinnamon and salt. Stir into the pumpkin mixture, just enough to combine.

Heat a lightly oiled griddle or frying pan over medium high heat. Pour or scoop the batter onto the griddle, using approximately 1/4 cup for each pancake. Brown on both sides and serve hot.

Melt the butter in a large saucepan over medium heat. Stir in the sugar, buttermilk, vanilla, and cinnamon until smooth. Bring mixture to a boil. Once boiling, simmer for 2 minutes, stirring constantly. Add baking soda--it will cause the mixture to foam up. Cook for 30 more seconds and then remove from heat.

Allow to cool for 10 minutes before serving. Syrup will thicken as it cools. Store leftovers in an airtight container, in the fridge, for up to 2 weeks.