• Start by peeling, discarding seeds and dicing melon. Place melon cubes in a large container and add sugar. Combine.
• Cut the vanilla pod in half, scrape the inside seeds with a knife. Add this to the melon-sugar mixture.
• Take off lime zests with a very fine grater and squeeze the equivalent of a lime and a half. Put everything into the bowl with the other ingredients and combine.
• Let it stand at room temperature for 1 to 4 hours.
• Remove the vanilla pod and mix (you can decide to leave the melon cubes). Put the vanilla back in the preparation (and cut it into pieces which will allow you to have one piece of vanilla pod in each jar of jam for decoration).
• Bring to a boil and skim. Let the jam cook for 15 to 20 minutes until it comes to the jelling point and the texture changes.

Two methods to see when the jam is ready:

• 1 / dropping a few drips on a plate and leaning the plate. If the jam “runs away” as we say in French you have to leave the jam on the gas for a while;
• 2 / as my mom does : putting a big drip between two fingers (thumb and index), be careful not to burn yourself, and spreading apart both fingers. If the jam that is on each finger takes time to separate, and seems to hang heavly, then it is ready.
• To help the jam fix and also for the nice texture it gives, a few minutes before the end add a teaspoon of agar agar (I sprinkle it through a tea strainer so that agar agar falls as rain) and let cook a few more broths (30 seconds are normally enough).
• Pour into jars (previously sterilized by pouring into boiling water in the jars and on the lids if you don’t have a sterelizing machine), close by squeezing hard and let it cool down, pots upside down.