Lime and Rum Marmalade

This marmalade was inspired by some home made marmalade I had in Portugal. it comes into my top 3 of hotel/B&B jams. We were staying at a Turismo Rurale in a Qunita. It had lovely gardens that led to plantations of limes and other fruits all grown organically and eventually down to the sea.
This is no insipid sweet green jelly. It has an intense flavour, a rich deep colour and is not overly sweet. If you prefer it sweeter use half as much sugar again. I did n’t have a complete recipe so have been experimenting. This is my fourth attempt and now very close to the original.
 I thought of adding rum, I don't think it was in the original

720g limes
350g Muscavado sugar
750g Golden granulated sugar
700 ml water
Rum to taste (add some to the marmalade as well if you like!)

Put 5 clean jam jars with lids separate on a baking tray and into an oven on gas mark 1
Leave the limes whole and cook with the water for 15 min in a pressure cooker with lid and weights on.. (In the original marmalade the limes had been sliced first. Nice but too much faff for me.)
Or simmer in an open pan until the rinds are soft, stir and make sure it doesn’t boil dry.
Put in a food processor or Thermomix and process so that the peel breaks into smallish pieces. I return this to the pressure cooker, add the sugar, keep stirring and boil fast  until the setting point is reached. Usually when the thermometer says 105C You’re there when a sample will set on a saucer. I love that bit as I usually get to taste several samples before it is ready. you can do the boil in the TM but I find it takes a bot longer.
Pour into the hot jars and immediately screw the lids on tightly.

I have experimented by adding some rum to one of the jars. I didn’t put the lid on this one, waited till it was cool and added some rum.
About 5 teaspoons (25ml) per 1lb pot (454g) tastes good.