Blanch, peel and roughly chop tomatoes.
In a food processor, dice the bell peppers, cucumbers, jalapenos, onion, cilantro and garlic.
Combine everything in a large stock pot.
Add marjoram and vinegar.
Bring to a boil, then reduce heat and simmer for 20 minutes.
Ladle into clean, hot pint jars, leaving ½-inch headspace.
Remove air bubbles and adjust headspace if needed.
Wipe rims of jars with a dampened, clean paper towel; apply two-piece metal canning lids. Process in a boiling water canner according to your elevation.