[bshimmin]

While I broadly agree with this, I would say that my own attempts at making mint sauce were fairly disappointing in comparison with shop-bought - Colman's mint sauce is an awful lot nicer than anything I was able to make, and (though I've never tried to make it) I bet their wonderful mustard is too.

You will probably also not be able to make at home anything all that similar to the mayonnaise you buy in a shop, though what you can make at home will almost certainly be equally as nice (my children were confused by the yellowish colour of home-made mayonnaise, which is sort of backwards since the confusing thing ought to be why shop-bought mayonnaise is white!).