Wash 9 half pint canning jars and cover to keep them hot.
Fill a water bath canner almost half full of water and bring to a simmer.
Place 9 lid flats in a small pan of hot water.
In a dutch oven, combine the strawberries and the butter. Stir in the pectin. Bring to a full rolling boil over high heat, stirring constantly. Stir in sugar; return to a full boil. Boil and stir for about a minute. Stir in the basil quickly.
Remove from heat and skim off foam. Ladle the hot mixture into 9 half pint jars, leaving 1/4 inch head-space. Remove air bubbles, adjust head-space by adding more hot mixture if necessary. Wipe the rims. Center lids on jars and screw bands until fingertip tight.
Place the jars into the canner of simmering water, make sure they are completely covered with water. Bring to a boil and set a timer for 10 minutes. Shut off heat when timer goes off, remove lid and wait 5 minutes before removing jars from the canner. Set on a towel and leave for 24 hours.
Date and label jars. Store in a cool dry area.
