As it turns out, beer floats are a thing!
Chef John of Food Wishes makes these two types of beer floats that look absolutely amazing.
You could also use your favorite domestic beer, such as Budweiser or Miller.

Image By: Food Wishes Via YouTube
Then, you will add a little bit more stout over the top of your float.
There is also a recipe for a float made with raspberry lager and uses vanilla ice cream.
Both of these taste excellent.

I made the Guinness float for my husband and he loved it!
