A friend of mine said when I keg my vanilla porter I should put in a few shots of capt Morgan in the corny keg to finish it off. Is this a good idea???
It's all personal preference. Captain Morgan is an interesting choice in my opinion. Shouldn't hurt the beer either. Not really sure if a few shots would make a noticeable difference either.
Since this is your first I would keg it without it. Then maybe just serve it with a splash of it to see if you like it? Like a boilermaker but with a little rum...