Puree chilies in small food processor or blender. Place milk, cream, 1/4 cup of the sugar and pureed chilies into medium saucepan; blend well. Heat over low heat 40 minutes, stirring constantly, or until cream mixture forms small bubbles around sides of pan. Do not allow to boil. Remove from heat.
Combine the remaining 1/2 cup sugar with the egg yolks until blended. Gradually whisk about 1/4 cup of the hot cream mixture into egg yolk mixture to temper or prevent yolk from curdling. Whisk tempered yolk mixture into saucepan with remaining hot cream mixture. Return pan to low heat, stirring, until slightly thickened or mixture coats back of a spoon, about 5 minutes. Pour hot mixture through a fine sieve or cheesecloth. Pour into shallow bowl to cool quickly.
Freeze cooled egg mixture in ice cream maker following manufacturer’s directions. Store in airtight container in freezer. Serve garnished with Reddi-wip. Add sprinkle of red pepper flakes and sprig of cilantro, if desired.