FOR THE CUPCAKES:

1. Heat oven to 375 degrees F.
2. Cream butter, vanilla, and sugar together in a stand mixer.
3. Add bourbon and egg whites and mix briefly to combine.
4. Add flour and salt and stir to combine.
5. In a separate small dish, combine apple cider vinegar, milk, and baking soda. Stir to combine. Mixture will foam up a bit.
6. Add milk and baking soda mixture to stand mixer bowl a bit at a time, with the mixer running on low. Mix batter until everything is just combined.
7. Line two muffin pans with cupcake liners and scoop batter into each liner until it's about 2/3 of the way full.
8. Bake cupcakes at 375 F for 12-15 minutes until a toothpick comes out clean. Transfer cupcakes to a wire rack to cool completely before frosting.

TO FROST:

1. Cook bacon until crispy and set aside. I like to bake mine at 375 F on a single layer on a rimmed baking sheet until it's crispy, then set on a plate with paper towels to drain any grease.
2. When cupcakes have cooled completely, make the frosting.
3. Cream butter, vanilla extract, and seeds from the vanilla bean together in a clean stand mixer bowl.
4. Add bourbon and milk to bowl and mix briefly to combine.
5. Add powdered sugar to bowl one cup at a time, mixing on low speed between each addition so powdered sugar doesn't fly everywhere. If frosting is too thick, add a tablespoon or two of milk and mix to thin it out. Too thin? Add a bit more powdered sugar.
6. Frost cooled cupcakes. I swirled frosting on to cupcakes with the back of a spoon this time to make nice dents on top for the bacon, but you could also pipe it on.
7. Crumble cooked bacon and place a few pieces of crumbled bacon on top of each cupcake. Serve immediately.