In large bowl with wire whisk or fork beat chopped basil oil vinegar mustard salt and sugar until blended set aside In 5-quart saucepan over high heat heat 3 quarts of water to boiling
Fill a large bowl with ice water
Meanwhile cut small x in stem end of each cherry tomato
Add 1 pint cherry tomatoes to boiling water
After 5 seconds with slotted spoon remove tomatoes to ice water to cool them
Repeat with remaining cherry tomatoes heating water in saucepot to boiling before adding each pint of cherry tomatoes and adding more ice to water in large bowl as needed