4kggreen tomatoes(finely chopped. 4 US quarts / 8 lbs. Measured after prep.)
1.5kgapple(chopped. Measured after peeling, coring and chopping somewhat finely. About 4 cups / 3 lbs. Measured after prep. 2 kg / 4 lbs before peeling.)
Put on stove, bring to a boil, then lower to a simmer and let simmer uncovered for about 40 minutes until ingredients are tender and the mixture has thickened a bit. Stir often.
Ladle into 1 litre (1 US quart / 32 oz) jars.
Leave 2 cm (½ inch) headspace.
Debubble, adjust headspace.
Wipe jar rims.
Put lids on.
Process in a water bath or steam canner.
Process jars for 15 minutes; increase time as needed for your altitude.