Canadian Maple Pecan Cake

Preheat oven to 350ºF. Butter and flour two 9-inch cake pans.
In a large mixing bowl, combine flour, soda, salt and baking powder.
In another bowl, combine buttermilk and maple syrup.
With an electric mixer set at med-low speed, beat 6 ounces of the butter (12 tablespoons) and the granulated sugar until light and fluffy, about 5 minutes.
Beat in 1 teaspoon of the maple extract and the vanilla.
Beat in eggs one at a time, beating well after each addition.
Reduce speed and beat in flour mixture in three parts, alternating with buttermilk mixture.
Stir in the chopped pecans.
Pour into prepared pans.
Bake in a preheated oven for about 25 minutes or until toothpick inserted in center comes out clean.
Cool 10 minutes in pans. Remove from pans and cool completely on wire racks.
Meanwhile, sift powdered sugar.
With an electric mixer set at medium speed, beat remaining 8 ounces butter (16 tablespoons) until creamy.
Reduce speed to low and gradually beat in powdered sugar.
Beat in remaining ¼ teaspoon maple extract.
With a spatula, fold in marshmallow crème.
Put on cake layer on a serving plate. Spread top with about ¾ cup frosting. Top with remaining layer. Spread top and sides with remaining frosting. Decorate with pecan halves.