Patricia, I've never had Hot Buttered Rum and honestly, it doesn't sound very good, but here are a few recipes I found for ya:
2 cups firmly packed brown sugar
1/2 cup butter or margarine
1 pinch salt
3 sticks cinnamon
6 whole cloves
1/2 teaspoon ground nutmeg
2 cups rum
heavy cream -- whipped
ground nutmeg -- for topping
Put all ingredients, except rum and cream into crockpot. Add 2 quarts hot water. Stir well. Cover pot and cook on LOW for 5 hours.
Add rum; stir to blend. Serve from pot in warm mugs with a scoop of whipped cream and a dusting of nutmeg.
Single Serving of HBR - double or triple as needed:
2 or 3 ounces dark rum
Twist lemon peel
Sweet cider or water
1 tablespoon sweet butter
Put the rum, lemon peel, cinnamon and cloves in a pewter tankard or any heavy 12-ounce mug that has been rinsed in very hot water to warm it. Heat the cider or water to the boiling point and pour into the spiced rum. Add the pat of butter and stir well. Grate a little nutmeg on top. A cube of sugar may be added as well.