Wash apricots and thyme leaves.
Place a small plate in the freezer, this will be used later for jam testing.
Place the apricot flesh in a large, heavy based saucepan over low to medium heat and cook until the fruit has softened and completely collapsed. Stir and check the fruit regularly.
Add the sugar and increase the heat. Stir continuously ensuring the sugar dissolves. Cook fruit and sugar mixture at a rolling boil for about 5 minutes. Add the thyme leaves and combine them thoroughly with the jam. If using a sugar/candy thermometer the temperature should reach 104°C. Turn off the heat while you test the jam.
Drop half a teaspoon of jam onto the pre-prepared cold plate. Let it cool for a minute and then run your finger through the middle of the jam. If it crinkles and feels thick it is ready to be carefully transferred to warm, dry, sterilised jars. If not, continue to cook and continually stir and check. Seal jars and allow to cool completely.
This jam will keep for up to a year, at least. Refrigerate after opening.
I would recommend using a sugar/candy thermometer to take the guess work out of jam making.
Jam sugar can make the jam setting process more reliable. It is available from most major supermarkets.
This makes approximately 3-4 medium size jars, sterilise a few extra jars as it can be very frustrating if your jam is ready and you have run out of prepared jars.
If you have any left-over thyme you could make tiny wreaths with it.