In the bottom of a small mug, mix together the butterscotch syrup, rum and liqueur
Add one cup of sparkling non alcoholic cider
The butterbeer will foam up naturally, but if desired, you can top it with whipped cream.
Butterscotch Sauce Recipe
2 cups sugar
1 cup water
4 TB salted butter
1/2 tsp baking soda
1 cup hot water
In a tall sauce pot, combine sugar, the first cup of water and butter.
Turn on heat to medium low and stir until sugar melts.
Once the sugar has melted, stop stirring and turn up the heat to medium high.
Bring to a boil, swirling the pan to keep the mixture moving.
If needed, use a wet pastry brush to wash down crystals that form on the side of the pan.
Cook until the mixture is golden brown and caramelized, making sure to pull it off the heat before it burns.
Add the baking soda and stir it in (the mixture will bubble up).
Slowly pour in remaining hot water and stir until smooth.
If the mixture separates when the water is added, reheat it over low heat and stir until any sugar clumps melt.
This syrup can be made ahead of time and refrigerated, but it is likely to crystalize. Store it in a glass bowl or jar and gently warm it up in the microwave until the crystals melt. I'd highly recommend using the defrost setting. The sauce will make enough for about 8 butterbeer servings.