Preheat oven to 350° F.
Halve tomatoes and place on a baking sheet cut side down. Roast 20 minutes then turn tomatoes over and roast an additional 10 minutes. Let cool. Slip skins off, then roughly chop.
Prepare boiling water canner. Heat jars in simmering water until ready to use, do not boil. Wash lids in warm soapy water and set aside with bands.
Combine tomatoes with all remaining ingredients except tequila, in a stainless steel pot. Bring to a boil, then lower heat to simmer, cook stirring frequently until plums soften and salsa thickens, about 20 minutes. Take off heat and stir in tequila.
Ladle hot salsa into a hot jar leaving a ½ inch headspace. Remove air bubbles. Wipe jar rim. Center lid on jar and apply band, adjust to fingertip tight. Place jar in boiling water canner. Repeat until all jars are filled.
Process jars 20 minutes, adjusting for altitude. Turn off heat, remove lid, let jars stand 5 minutes. Remove jars and cool 12-24 hours. Check lids for seal, they should not flex when center is pressed.