The idea is that you make this flavored simple syrup ahead of time, and then use some of it to make each drink. This Root Beer Float recipe calls for heavy cream instead of ice cream, and fizzy water, so it is probably like the soda fountain drinks we enjoyed as youngsters. I might try it without the vanilla cognac because I don't have any, but I might pick up a bottle sometime so I get the full effect.

Root Beer Float

2 ounces caramel-root beer simple syrup (recipe is below)
2 ounces vanilla cognac
2 ounces heavy cream
Ice
Club soda or seltzer water

In a cocktail shaker, combine the syrup, cognac and cream. Fill with ice. Shake, then strain into a tall glass. Top with club soda or seltzer. Serves 1.

Caramel-Root Beer Simple Syrup

1/4 water
1 cup sugar
Four 12-ounce cans root beer
1 vanilla bean, split and seeds scraped into the syrup

In a large saucepan over medium-high, combine the water and sugar. Bring to a low boil and cook, without stirring, until the syrup is a deep amber.

One at a time, slowly pour in the root beer. The mixture will sputter and froth. Add the vanilla bean, then bring the mixture to a simmer and cook until reduced to 2 cups. Remove from the heat and let cool. Remove the vanilla bean. Pour the syrup into an airtight jar and refrigerate for up to 2 months. Makes 2 cups.