I moved last year and we do not have any fruit or enough of berries for sweet preserves. Then we got watermelons ready… one a day
. No, I do not cook the flesh. But the watermelon rinds and a store bought lemon make wonderful preserves or candies, if you drain syrup and let the rest to dry, if you wish.
600 g watermelon rinds, cleaned and cut. (remove all colored flesh and peel top layer from the rind and slice 1/2 long, 1/4 thick)
400 g of sugar
1 medium/large lemon
Mix prepared watermelon peels and sugar in a pot and let it stay for 3-4 hours.
Wash and peel lemon thin (just zest) and make a juice from the rest of the lemon. Make sure no seeds get in, even small ones, they will give bitter taste.
Add lemon juice and zest to the watermelon rinds (they should be swimming in syrup by now), bring to boil and keep on low for 30 min. Let it cool completely. Repeat boil/cool down cycle 2 more times. After that you can discard zest and just put the rest in a clean jar, no canning needed if you keep it refrigerated.