Our redaction was based on the one from A Taste of History, but
I have since adjusted the amounts slightly. Their redaction called
for one part mustard to one part vinegar to three parts butter; I have
since reduced the butter to approximately 1.5 parts.
This sauce will congeal if it cools; it will still be edible (and quite
tasty), but the texture is more pleasing when served warm. (However,
if you get it too warm and it boils, the butter will separate out, which
is equally unpleasant.) I often use a candle-powered fondue pot to
both prepare the sauce and keep it warm for serving.
I prefer a whole-grain mustard for this sauce, but try to stay away
from the dijon mustards, as they are a little sharp. There are a
couple of "stout" and "porter" mustards that work very well; in a pinch,
I suppose yellow mustard would do, though I haven't tried it.
For vinegar, I've used balsamic, which gives the sauce a very nice flavor,
but which turns it a rather unpleasant, nasty brown. Recently, however,
I've been able to find some nice white or golden balsamic vinegars that
have much the same flavor, with a more pleasing color. Cider or white
wine vinegar would also work.
For an extra touch of decadence, visit your local oriental market and
pick up a few cans of quail eggs to serve with this sauce.
The above recipe allows for extra sauce, because we quickly discovered
that while it's very good on eggs, it's also good on almost everything
else. We've had it on sausage, Fystes of Portingale, chicken, beef
... even vegetables.
And just to prove that the sauce is truly versatile ... I was going
through some old family recipes when I came across my mom's recipe for
mustard barbecue sauce, which I loved as a kid. Guess what?
It consisted of mustard, vinegar, and butter! So it also works as
a marinade and basting sauce for the grill (it's excellent on chicken,
by the way ...).