Cherry Bon-Bon

A fountain frappé rather than a soda: no carbonated water, just syrup poured through very fine shaved ice with ice cream at the bottom and top. The whole thing lives or dies on the texture of the ice.

• The duplicated lineThe phrase "shaved ice. Pour 2 ounces cherry syrup over the ice" appears twice in the source text, evidently a duplication rather than a second layer. Build it once: ice cream, ice, syrup, ice cream, cherry.
• Shaved, not crushedFountain shaved ice was cut fine enough to pack like wet snow, so the syrup soaked through rather than draining to the bottom. A blender or an ice shaver gives the right result; crushed cubes from a bag leave you with a pool of syrup under loose chunks.
• MeasuresTwo ounces is a quarter cup. A "small spoonful" of ice cream means roughly a tablespoon or two, not a scoop, both top and bottom.
• The glassAn 8-ounce stemmed glass, as the recipe specifies. It is packed nearly to the rim with ice before any syrup goes in, so a straight tumbler of the same volume works but shows the layers less well.
• Cherry syrupPeriod fountain syrup was a heavy sugar syrup, sweeter and thicker than a 1:1 simple syrup, flavoured with cherry juice or extract. Modern cocktail or Italian soda syrups are close enough; thin grenadine will taste flat against the ice.
• Maraschino cherriesOriginally these were Marasca cherries preserved in maraschino liqueur. The bright red, brined and sweetened American product is a later substitute, and is what you are likely to find now.
• Serve at onceMakes one drink. Assemble it and hand it over; within a few minutes the ice slumps and the syrup collects in the foot of the glass.