Simpson, married to his childhood sweetheart for almost 19 years, had walked out on his wife and kids and into the arms of a younger woman. The breakup surprised his wife, his friends and even Simpson himself. Looking back, he says, it was a classic midlife crisis.
In that we have already provided the definitive answer to this question elsewhere (relying on rum extract), we assume your follow-up is seeking a non-alcoholic substitute for rum (as extracts can be as alcoholic as or more alcoholic than the spirits they replace).
If you use a silver rum, your vanilla will have a purer taste suitable for whipped cream or custard sauces. I get rum that is bottled in glass, because I think plastic imparts an off flavor. Your basic recipe will use a fifth less about a 1/2 cup of rum, four vanilla beans and 1/2 cup of organic sugar.