Bring a large pot of water to a boil. Fill a large bowl with ice and cold water. Drop tomatoes into boiling water and cook 30 seconds. Using a slotted spoon, transfer tomatoes to ice water to stop cooking. Drain and peel. 

 

Combine 4 cups water, lemon juice and sugar in a medium saucepan. Bring to a boil, then remove from heat.

 

Put tomatoes and basil into hot, sterilized canning jars. Cover with hot water mixture, leaving 1/2 inch space at top. Wipe off rims of filled jars with a clean, damp kitchen towel, then top with lids and screw on “finger tight” (just screwed on with your fingertips, not cranked tight with your palm).

 

Put sealed jars on rack in canner or pot and add enough water to cover by 2 inches. Bring to a boil, covered, then boil 45 minutes. With tongs, transfer jars to a towel-lined surface to cool.

 

(For more detailed directions on canning, cooling, and storing, as well as safety tips, look here.)