In medium saucepan over medium heat, heat half and half until very hot, but not boiling, stir often. Remove from heat, set aside.
Place egg yolks and maple syrup in mixing bowl. Attach wire whip to mixer. On medium speed mix until well blended and slightly thickened. Continue with mixing speed gradually add half and half, mix until blended.
Return half and half mixture in a medium saucepan, cook over medium heat until small bubbles around the edge of pan and mixture is steamy, stir constantly. Do not boil.
Transfer mixture into a large bowl, stir in whipping cream, maple extract, salt and vinegar. Cover and chill for 8 hours minimum.
Follow ice cream maker instructions, until desired thickness. Freeze in an airtight container.