Preheat oven to 350º.
Line a muffin pan with paper liners. In a large mixing bowl, whisk together flour, baking powder, baking soda, 3/4 cup cocoa and salt. Set aside.
In the bowl of a standing mixer, cream together the 3 tablespoons butter and sugar until light and fluffy. Add the eggs one at a time, beating well with each addition, then stir in the 1 teaspoon vanilla - divided. Add the flour mixture alternately with the buttermilk; beat well after each addition. Fill the muffin cups 3/4 full.
Bake for 15 to 17 minutes in the preheated oven, or until a toothpick inserted into the cake comes out clean. When cool, frost with Bacon Chocolate Frosting.
Bacon Chocolate Frosting:
In the bowl of a standing mixer, beat 1/4 cup butter - divided and 1/2 cup cocoa -divided together until combined. Add milk and 1 teaspoon vanilla. Beat until smooth. Gradually beat in confectioner's sugar until desired consistency is achieved. Adjust with more milk or confectioner's sugar if necessary. Fold in chopped bacon. Frost chocolate cupcakes and top with a piece of crisp bacon for garnish.