Bring 2 pots each filled with 8 quarts of water to a boil. Fill a bowl full of ice water. Place 1/2 of the tomatoes in one of the pots of boiling water for 1 minute. Remove from boiling water and place in ice water. Repeat with other half of tomatoes.
Place passata in a saucepan and heat. Add 2 tablespoon of bottled lemon juice or 1/2 teaspoon of citric acid to each sterilized quart jar. When tomatoes are cool enough to handle, carefully remove skin and place tomatoes in sterilized quart jars. When jars are filled with tomatoes, pour hot passata in to cover the air gaps. Top the tomatoes and passata with basil leaves and olive oil and seal jar with sterilized, self-sealing lids.
Prepare pressure canner according to manufacturer's instructions to 11 pounds of pressure. Place the jars in the pressure canner and process for 25 minutes, until they are properly sealed. Carefully remove jars from canner and let stand until room temperature.
**This recipe differs slightly from the one seen on this episode. This recipe has been adjusted for U.S. consumption and follows USDA guidelines for canning tomatoes.