Preheat oven to 350°F. Line cupcake pan with paper liners.
Whisk together flour, white sugar, cocoa powder, baking powder, and salt in a mixing bowl. Set aside.
In another bowl, mix buttermilk, tequila, liquefied coconut oil, lime juice, brown sugar, coffee, eggs, and vanilla. Mix well to combine.
Pour wet ingredients into dry, and blend using an electric mixer until incorporated. Pour batter into cupcake liners until 2/3 full. Bake 20-25 minutes or until a toothpick comes out of the cupcake cleanly. Because of all the liquid in the batter, this will take longer than normal.
Remove cupcakes from cupcake tins and allow to cool on a rack for at least 10 minutes.
When cupcakes are cooled completely, blend remaining coconut oil until it becomes very white and creamy. Add 1 cup of confectioners' sugar, vanilla, and 2 tablespoons of milk and beat until smooth. Add all remaining ingredients except for coconut flakes and blend on low speed until desired consistency is reached.
Once cupcakes are completely cooled, top with frosting. Sprinkle coconut flakes on the top of each cupcake so it sticks to the frosting.
Store cupcakes in refrigerator (coconut oil tends to liquefy at room temperature, which will make the frosting run).