For the Honey Nut Cheerio-Infused Cream:
In an airtight container, combine cereal and heavy cream. Cover and refrigerate 1 hour, stirring occasionally. Strain liquid through a chinois, pressing gently on the cereal.
To Assemble and Serve:
In a cocktail shaker, combine Cognac, rum, honey syrup, orgeat, Sherry, ¾ ounce Honey Nut Cheerio-infused Cream, egg yolk, and bitters. Dry shake. Add ice to shaker, and give a good long shake. Using a hawthorne and a fine strainer, strain drink into a small fizz glass.