Start out with lots of tomatoes. It doesn't matter if they have blemishes, marks, or whatever, most of them will be used. Wash them up but do get rid of any that are in really bad shape.
Drop them into boiling water for about 30 seconds or so. Small batches at a time.
Then drop them into cold ice water. This helps the skins peel right off.
When you get a whole sink full...
...It's time to slip them out of their skins. Most times the bad parts will come right off with the skins, if not then simply cut out the bad areas.
I then take a small cheapy knife and cut out the core. Check the bottom and remove it if it hasn't already slipped off with the skin.
Then cut them into quarter size pieces. You can leave them whole, half, or whatever size you prefer.
Fill up your jars, pack them in there but not too crammed. Today I did quart jars but I often do larger 1 1/2 quart jars or smaller pint jars. The jars do not have to be sterilized because they will end up in the pressure canner. Just make sure they are clean with no nicks or cracks.
Once all your jars are filled...
...It's time to add 2 tablespoons of lemon juice. This is a must because tomatoes are considered "low acid." I won't explain the details here but for safety's sake add the lemon juice. You won't taste it I swear.
Then 1 teaspoon of coarse salt. The salt is optional but it does enhance the flavour.
I like to pour tomato juice in so my canned tomatoes don't end up looking watery. This too is optional. Yes I could make my own juice but I find it much easier to buy the cans :) I used about 2 and a half cans for 24 quarts.
Take a, okay I have no idea what this thing is called, but take it and run it around the inside of the jar to get rid of the air bubbles and pour in more tomato juice if necessary.
Wipe the rims with a hot paper towel until they are squeaky clean. Check for any stray seeds.
All jars should be filled leaving a 1 inch headspace, adjust if necessary. Place your hot lids on and then screw rings on fingertight. Check your manual for how much water to add to your pressure canner, mine is about 2 to 3 inches, yours may vary. Never place cold jars into boiling water because they will break. Remember cold jars = cold water, so add your water, then your jars, and then turn on the heat. I add a bit of vinegar to the water to keep the white off the jars.
Don't forget to vent your pressure canner. When the canner is up to pressure, process at 10 pounds for 10 minutes.
Wait 'til the pressure drops to zero, remove jars, and let sit undisturbed for 24 hours. Check seals, remove rings, wash in hot soapy water, and sit back to admire all the work you've done :)