FOR THE MUFFINS: Melt butter and allow to cool slightly while you prepare the rest of ingredients. In a large bowl whisk flour together with granulated sugar, baking powder and salt. In a medium bowl whisk the eggs together with the buttermilk, vanilla and cooled, melted butter. Using a rubber scraper, stir liquid ingredients into dry while making sure that ingredients at the bottom of the bowl are thoroughly incorporated. Gently fold in cranberries and pecans until evenly distributed.