Pressure Cooker Marmalade, Fast! - cooking recipe

Ingredients

2 lbs lemons
2 -4 lbs sugar, to taste
water (or a mixture of the two in the minimum amount required by your pressure cooker's manufacturer) or citrus juice (or a mixture of the two in the minimum amount required by your pressure cooker's manufacturer)

Preparation

Thinly slice the clean fruit. A mandoline is ideal for the job. Remove end slices, as they are mostly bitter pith. Be careful to remove any seeds or pieces of seeds. Cut the slices into quarters. Weigh the prepared fruit; you will need to know the weight when it comes time to add the sugar.
Place the prepared fruit and the water or juice in the pressure cooker, lock down the lid, and bring it to pressure on high heat, if using a stovetop pressure cooker. Decrease the temperature and cook at high pressure for ten minutes. Remove from heat and allow pressure to dissipate naturally. If using an electric pressure cooker, cook on high pressure for ten minutes and use natural release.
Calculate how much sugar to add. You will need to use one to two times the weight of the prepared raw fruit. Start with an equal amount, then add more to taste. Mix the sugar into the warm cooked fruit and stir to dissolve. Bring to a boil, and cook until the mixture reaches 212 degrees Fahrenheit, 100 degrees Celsius.
Fill clean, sterile jars, leaving 1/2 inch headspace, apply lids and rings and process in a boiling water bath for five minutes. If not processed in a boiling water bath it must be kept under refrigeration.