Blueberry & elderflower jam

Put a small plate in the freezer (this is for the jam test later on). Stir together the berries and sugar in a medium casserole or stainless steel pan. Set the pan over a low heat and stir occasionally until the sugar has dissolved.

Take off the heat and crush the berries lightly with a potato masher. Stir in the lemon juice and a pinch of salt, then return to the heat and bring to a vigorous boil. Bubble for 10 minutes, skimming off any scum from the top.

Take the pan off the heat and place 1 tsp of the jam on the chilled plate. Leave for a few seconds, then push the jam edge with your finger. It should be softly set and should part cleanly through the middle. If the jam is too loose, return the plate to the freezer and bubble the jam for 2 more minutes before testing again. Repeat boiling and testing until ready, then take off the heat and stir in the cordial.

Let the jam stand for 5 minutes, then ladle into clean, sterilised jars (see cook’s tip). Seal while warm and store in a cool, dark place for up to 6 months. Once open, store in the fridge.