Heat oven to 350 degrees. Line standard size cupcake pans with liners to make 24 cupcakes. Set aside.
For cake: Sift together flour, baking powder, soda, salt, and spices into a bowl; set aside. In bowl of electric mixer cream together butter and brown sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Stir in flour mixture, alternating with buttermilk. Stir in vanilla.
Divide batter into cupcake liners in pans. Bake for about 14 minutes or until a toothpick inserted into center comes out clean. Remove from oven and cool on wire rack about 5 minutes, then turn out cupcakes from pan and cool completely before frosting.
For Frosting: Sift powdered sugar and cinnamon into bowl; set aside. In bowl of electric mixer, beat together melted butter and ½ cup of the sugar mixture. Beat in egg white and salt. Add remaining sugar mixture, milk, and vanilla. Beat until of spreading consistency. Frost cupcakes. Makes 2 dozen cupcakes.
Note: This is enough frosting to spread on cupcakes, but if you like a lot of frosting and want to use a pastry bag to make large, high swirls, the frosting should be doubled.
Recipe by The Culinary Cellar at https://theculinarycellar.com/hallmark-movie-recipe-truly-madly-sweetly/