In a large bowl, cream butter and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in vanilla. Combine the flour, cinnamon, baking powder, baking soda, salt and nutmeg; add to the creamed mixture alternately with buttermilk, beating well after each addition.
Fill paper-lined muffin cups two-thirds full. Bake at 350° for 17-22 minutes or until a toothpick inserted in the center comes out clean. Cool for 10 minutes before removing from pans to wire racks to cool completely.
For frosting, in a small bowl, beat butter and shortening until fluffy. Beat in maple syrup and salt. Add confectioners’ sugar; beat until smooth. Frost cupcakes. Sprinkle with bacon if desired.