You will need:
1 bushel of tomatoes
16 to 18 1 L mason jars with lids
fresh basil leaves
large pot or two (to cook the tomatoes)
very large pot or canner (to boil the canned tomatoes in)
Fill the 1L mason jars with tomatoes half way, stuff in a few fresh basil leaves and then continue to fill the jars until 1 inch from the top. Cover with snap lid. Continue to fill all jars this way.
First buy one bushel of Roma (or plum) tomatoes from your local farmer, farm store or market. One bushel will make between 16 and 18 1L jars of tomatoes. If you are not "making the tomatoes" that day you will want to spread the tomatoes out on a large surface so they do not ripen unevenly or rot.
(In the above picture, I also have some garlic and red peppers, which I cut and froze to use throughout the winter.)
Fill your sink with water and wash the tomatoes. Using a small, but sharp pairing knife, cut the tomato in half. Remove the stem of the tomato and the little hard part the stem grew out of. Then with your fingers, scoop out the seeds and slushy stuff inside of the tomato into a strainer with a bowl underneath. Now you can cut that tomato half into about 4 or 6 pieces. Place all the tomato pieces into a bowl.
(Above is my cousin Chris, doing a fine job helping cut the tomatoes)
Next dump the diced tomatoes into a large pot and cook the tomatoes on medium-high heat. Once they start to boil, reduce heat to medium-low and simmer approximately 25 to 30 minutes. Once they are cooked down to a nice thick, chunky sauce, remove from heat. Using a hand blender, blend the tomatoes until a consistent sauce.
Place a cloth at the bottom of the canner or pot and then place the jars in. Fill the pot with water until tops of jars are covered. Cover with another cloth. Bring water to a boil and boil for 30 minutes. Then remove jars and place on flat surface for 24 hours, undisturbed. Snap lids should be curved downward to demonstrate complete seal. DO NOT retighten lids. Remove screw bands and and dry bands and jars. Replace band loosely on jar and store in a cool, dark place. Enjoy making homemade sauce year-round like a true Italian!