Wash the apples well, core and peel them.
Cut in cubes of about 4 cm
Mix the apples with sugar, stir well and let marinate for 1 or 2 h. This will help to remove the water from the apples making it easier to cook
Cook the apples for 20 min on moderate fire: remove from the fire every 2 minutes
Cook the apples for 10 min on a low flame: remove from the fire every 20 seconds, watch that it does not stick. When it starts to stick turn off the fire and let it rest for 40 min
Cook the apples for 10 min more, first moderate fire stirring constantly. When it starts to boil, lower the heat and continue stirring constantly
Test if it is cooked, if it is not ready, cook for 10 more minutes or if it sticks we can let rest another 40 minutes and repeat the procedure
When it is cooked use the potato masher to mash everything well
To put it in pots it has to be boiling over low heat. Fill the pots in hot and put the lid on immediately, always stirring the jam that is on the fire so that it does not stick
Put all the pots face down
In the next 2 days watch that all the pots have done the vacuum seal, pressing the lid you can see that those who are done have a pressed lid. Those who have not done the vacuum seal will have to be consumed in the next couple of days or if you prefer you can boil in a water bath to ensure conservation.