Preheat oven to 400° F and place a 9" cast iron skillet inside to preheat also.
In large bowl whisk together cornmeal, flour, baking powder, baking soda, salt, brown sugar, and pumpkin pie spice.
Add pumpkin puree, eggs, sour cream, and pumpkin beer and mix until just combined.
With an oven mitt, remove the hot cast iron skillet from oven and add the 2 Tbsp. butter. Swirl around in pan until it is fully melted and pan is completely coated.
Pour batter into skillet and bake at 400° F for 18-20 minutes or until done and top of cornbread springs back with lightly touched.
Let cool for 5-10 minutes then slice and serve warm.