Preheat the oven to 350°F
In a mixer, cream together the butter and sugar until light and airy.
Next, mix in the eggs one at a time, incorporating each until fully mixed and light yellow.
Next, add in the pumpkin puree and vanilla extract. Mix until combined.
In a separate bowl, mix together all the dry ingredients: Flour, Soda, and all spices.
Alternate mixing in half of the dry ingredients, then the buttermilk, then the rest of the dry ingredients until everything is fully combined.
Grease a 9x13 cake pan with butter or pan spray. Pour batter into greased pan and spread evenly.
Bake for 20-30 minutes or until a tooth pick inserted into the center of the cake comes out clean.