2 tablespoons butterscotch ice cream topping
10 fluid ounces seltzer water
2 scoops vanilla ice cream
Spoon butterscotch topping into a tall glass. Whisk 1 to 2 fluid ounces seltzer water into butterscotch topping until topping is slightly thinned. Add the remaining seltzer water until glass is 3/4 full. Gently scoop ice cream into glass.