Preparation In a large heavy saucepan combine the corn, the cream, and the granulated sugar and simmer the mixture, covered, for 20 minutes. In a food processor, or in a blender in batches, purée the corn mixture and strain the purée through a fine sieve set over the pan, cleaned, pressing hard on the solids. Add the milk and the bourbon and bring the mixture just to a boil. In a bowl whisk together the egg yolks and the brown sugar, add the corn mixture in a stream, whisking, and pour the mixture back into the pan. Cook the custard over moderately low heat, stirring, until it registers 170°F. on a candy thermometer, strain it through the sieve set over another bowl, and let it cool completely. Freeze the custard in an ice-cream freezer according to the manufacturer's instructions.