This thread is a follow-on to a post I made in the "Underwood Brisling Sardines in Mustard Sauce?" thread in the General Chowhounding Topics forum. Since the focus is on the recipe for a sauce, instead of the Underwood product, I thought it warranted a new thread here.
My previous post reported an attempt to make a suitable mustard sauce for smoked sprats (brisling) in oil, which are generally available, to eliminate dependence on the sauce provided by a particular producer of sardines, thereby avoiding the painful withdrawal symptoms caused by the termination of the mustard sauce product. This post describes in more detail how I am attempting to develop an ideal mustard sauce for smoked sprats. Suggestions from other lovers of sardines with mustard are invited.
I have long eaten sardines with mustard, but always with off-the-shelf prepared mustard, never prepackaged in mustard sauce. Despite there being scores of mustards available, this has never been entirely satisfactory. Reading the Underwood thread made me realize that the mustard sauce should have a different character than mustard in a jar — it should be thinner so the fish would be swimming in it, instead of thick enough to stick to the bread as is typical for a (for example) roast beef sandwich, and it should have a more complex flavor than the simple mustards one would use for frankfurters or ham and swiss sandwiches. Thus a custom sauce is required.
My first recipe (in the other thread) used only ingredients I had on hand, which are readily available. It was based on Dijon mustard which, while certainly an excellent product, somehow just seems wrong for sardines. This week I had the opportunity to go to the international market where I get my sprats, so decided to develop a new recipe using northern European ingredients. I call this:
Gary's Baltic smoked sprats in mustard sauce (No. 1)
One 160g tin of Riga Gold smoked Baltic sprats in oil. This a readily available product of consistent quality. The Baltic sprat is the same fish (sprattus sprattus) as brisling.
Löwensenf (lions mustard) Extra. This mustard from Düsseldorf is described as "extra hot." It is not. It is a blend of mild and hot mustard, as many prepared mustards are, but is so mild I can eat it straight out of the jar without any difficulty. It is a simple formula (mustard, vinegar, water, and salt), has a texture similar to Dijon, and so makes a suitable base.
I have not included dry hot mustard in this recipe as I did in my prototype, but will probably include it in future versions due to the mild character of this "extra hot" mustard. I think it preferable to adjust the pungency of a mustard sauce this way, rather than to search for another, hotter mustard to use as a base.
Raw, unfiltered apple cider vinegar. Mine is domestic (California), but I expect this would be about the same wherever it came from.
Lea & Perrins Worcestershire Sauce (accept no substitutes).
Polish beer (I used Warka, a lager). Obviously there are hundreds of beers one might use. I wanted to stick with a northern European theme, so chose this one. Use whatever suits you, but the important point is to use beer instead of white wine (which is in Dijon mustard).
Authentic dark Russian rye bread (the bread is dark, not the Russians!). I used Cinderella Dark Russian Rye from San Francisco. This is not dark like pumpernickle, but a medium browm like "dark" brown sugar. I wish it were sliced a little thinner, but otherwise perfect for this use.
Drain and reserve oil from sprats. Transfer sprats to paper towels (use at least three below) to remove excess oil. If you dislike the tails, remove them.
To 1/4 cup of Löwensenf Extra, add: 1 tsp apple cider vinegar, 1/2 tsp L & P, and 1 tsp of beer. Stir until thoroughly blended.
Add 1 tsp of reserved oil from sprats. Stir until thoroughly blended.
Now the sauce will be nice and creamy. Place the sprats in a suitable dish and cover with the sauce. Mix gently so as to cover the sprats with sauce without damaging them.
Let marinate for awhile until you can stand the wait no longer. It helps if you have had something else to eat recently.
Place sprats with mustard sauce between two slices of bread. Yield one sandwich. With the bread specified, it's a fat sandwich, which is necessary given the thickness of the slices (7/16").
Eat sandwich with remaining beer.