Place your sauce pan over medium heat and add together the cream, dark rum, maple syrup and vanilla.
Warm until you have achieved a gentle boil.
Remove from heat.
Separate your egg yolks from the white in different bowls and stir your egg yolks until smooth.
Slowly add rum, maple mixture into the egg yolks and stir until combined.
Pour your custard into ramekins or a glass that can go into a warm bath. Fill each cup to desired amount (half to ¾ full).
Put your ramekins in a deep tray (this is the bath) and pour the hot water into the tray, about ¾ of the way up the side of the ramekins.
Cover the tray in tin foil and place in a preheated oven of 325 degrees. Check after about 20 minutes. You want to test and see if your custard wiggles like "jello". If it does remove from the oven and cover with plastic wrap and place in the fridge. You cover it with plastic to prevent a skin from forming on the surface. If it doesn’t wiggle like "jello" put it back in the oven for 2-5 minutes. You can serve this dish hot or cold the next day.