Traditional apricot jam

This is my mother's recipe - it has no water. She believed adding water encouraged mould to grow.

Ingredients

1 kg	Apricot, ripe but firm (Main)
1 kg	Sugar
1	Lemon, large, juice of
2 tsp	Butter

Directions

1. Halve and stone the apricots. Layer them in a ceramic or glass bowl together with the sugar and lemon juice.
2. Cover and stand overnight. This keeps the apricots in good shape during cooking.
3. Next day, place the apricot mixture in a large, heavy-based stainless-steel saucepan.
4. Bring to the boil on low heat, stirring until the sugar is dissolved. Increase the heat slightly and boil for about 20 minutes, stirring often.
5. Scoop off some of the foam that forms on top into a bowl (this is excellent spooned over icecream or yoghurt).
6. Test for setting. If necessary, boil for an extra five minutes. Watch the jam care fully at this stage as, if it is not stirred, it will burn on the base.
7. When setting point is reached, stir in the butter. This will remove any remaining foam. Pour into hot, sterilised jars and seal.