Preheat the oven to 400°F and place a rack in the middle of the oven. Line a baking sheet with parchment paper.
In a large bowl, whisk together the flour, brown sugar, spices, baking powder, baking soda, and salt. Cut the butter into small pieces and blend into the flour mixture with a pastry blender or two knives. You want both pea-sized and larger chunks of butter, so don't over-blend. Stir in the chocolate chips.
In a separate bowl mix together the milk, pumpkin, and vanilla, and then add the mixture to the flour. Mix just until the dough comes together and is quite sticky. Resist the urge to add more flour.
Transfer to parchment-covered pan pat the dough into a circle about 1/2 inch tall. Cut scones into 8 wedges.
Beat together egg and milk and brush the tops of the scones it.