Georgina's True English Butter Tarts
Good tarts should have a light brown, bubbly, soft-crust, and should be gooey, with a bit of liquid (syrup) inside. They should not be jelly-like, or 'jammy'. The tarts will fall as they cool.
Do not substitute anything for the butter; this will affect the taste and consistency. Margarine will make them oily and wet.
Golden syrup is an English molasses-type product; it is clear and thick. Popular brand Tate & Lyle's(R) is preferable, but light golden corn syrup should make a good substitute if necessary.
Raisins or nuts can be added for a variation: place raisins or nuts into the shells, before adding the filling.