Preheat oven to 400 degrees.
In a medium mixing bowl, combine the dry ingredients and mix thoroughly.
In another bowl add the buttermilk, pumpkin puree, and vanilla extract. Whisk until even.
Beat in 2 eggs - one at a time until even.
Slowly beat the dry ingredients into the mixture. You don't want to overdo it here, and a lumpy batter is perfectly acceptable.
Fold in the cranberries.
Add muffin liners to muffin pan. Evenly add batter to each depression.
Bake for 25 minutes.