makes 5-8 pints, depending on how much you let it reduce during the cooking time

Perfect Restaurant-Style Salsa

A delicious, let's-scrape-out-the-bottom-of-the jar salsa that you can eat fresh or can for later

Ingredients

8 cloves garlic
2 cups chopped white or yellow onions (approximately 2 medium onions)
1/2 cup diced hot peppers (approximately 8 jalapeños or 2 serranos)
3 quarts peeled, cored & chopped Roma tomatoes (approximately 15 lbs or 30-40 tomatoes)
1 tablespoon ground cumin
2 tablespoons chopped fresh cilantro
1 teaspoon black pepper
1 tablespoon salt
2 tablespoons evaporated cane sugar
2 cups white vinegar (at least 5% acetic acid, preferably 7%)
1/2 cup lemon juice (must be commercially bottled, unfortunately, for this purpose)

Instructions

First, peel the tomatoes. (Don't remember how? Here's a quick and easy method.) Set aside in a large bowl.
Next, working in batches, add all ingredients to a food processor and pulse until the mixture is fairly (but not completely) smooth. This can be done according to your preference, but I prefer the largest pieces to be no larger than about 1/8-inch.
After each batch has been processed in the food processor, pour it into a large stock pot. When all ingredients have been added, bring to a boil over medium-high heat, then reduce heat to medium-low and simmer and reduce to thicken and intensify flavors (5 minutes - 2 hours), stirring frequently, especially as the salsa thickens.
To eat fresh, let the salsa cool and store in the refrigerator for up to two weeks.

To can for long-term storage, keep the salsa hot and continue with the recipe:
While the salsa is simmering, prepare your jars.
Wash eight pint jars, along with their lids and bands, in hot, soapy water; rinse and drain. Fill a water-bath canner with water and place the jars in the rack, making sure the water just covers them. Cover and bring to a simmer over medium heat. Let simmer for 10 minutes, then reduce heat and keep jars hot until you're ready to fill them.
Place the flat lids in a saucepan and cover with water; bring just to a simmer over medium heat (a magnetic wand is SUPER helpful for lifting them out when you're ready for them!) Simply set the screw bands near your work area, as there's no need to heat the bands.
When both the salsa and the jars are hot, ladle the salsa into the jars, leaving 1⁄2-inch headspace (not all jars may be used). Remove air bubbles and adjust headspace if needed, then wipe rims. Adjust lids and process 15 minutes at 0–1,000 feet altitude; 20 minutes at 1,001–6,000 feet; or 25 minutes above 6,000 feet.
Place several towels in a draft-free area and remove salsa jars to the towels after processing. Let sit for 12-24 hours, until all lids have popped and sealed. If any lids have not sealed within 24 hours, place them in the refrigerator and enjoy within a couple of weeks.

Notes

Note that volume measures are very difficult to be accurate since definitions of what a "chopped" onion or "diced" hot pepper might look like - if in doubt, use the SMALLER amount (e.g. if you're chopping hot peppers and reach 1/2 cup after only chopping 5 jalapeños, then don't add more - you've got enough)