A version of this recipe is in my book. I have made a few tweaks to it here. I hope you enjoy!
1. Preheat Oven to 350
2. Carefully measure and combine flour, cocoa, baking powder and salt.
3. Combine and mix well the sugar and softened butter. Then add and mix well the eggs and vanilla.
4. Pour the bourbon Into a medium sauce pan on low heat and add the chocolate morsels. Stir constantly, and do not allow to boil. Once the mixture is smooth, add milk and combine thoroughly.
5. Gently fold the dry ingredients and sugar mixtures, once well combined. Add the bourbon and chocolate mixture. This will result in a very stiff batter.
6. Use a spatula to transfer the batter to your 8x8 or 9x9 inch well coated baking pan, and bake. Use of the smaller pan will add approximately 12-20 minutes to the baking time or until toothpick comes out nearly clean.
*Note: The better the bourbon, the better your brownies will turn out. If using a 1/4 cup of a $60 bottle of bourbon is contrary to your sensibilities, consider using a cheap flavored bourbon. I haven't been disappointed yet and the combinations are nearly endless.
I'm just a guy suffering with an infatuation with gundogs since childhood. Forty some odd years later this is what you get.