Preheat the oven to 350°.
Line a 9x5-inch loaf pan with parchment paper.
With an electric mixer, beat butter, brown sugar, sugar, vanilla, buttermilk, pumpkin and eggs.
In a separate bowl, combine flour, salt, pumpkin pie seasoning, baking powder and baking soda.
Add dry ingredients to wet ingredients. Mix until just combined. Do not overmix.
Pour batter into the loaf pan.
Bake on the center rack of the oven for 60 minutes until a toothpick inserted comes out clean.
Remove from the oven and place on a cooling rack.