If you have clam juice in the house, use it along with the milk from Constance's recipe to add a wonderfully complimentary flavor to the fake crab.
In fact, that basic sauce recipe is called a Bechemel and is one of the mother sauces (also called a grand sauce). This is used to make a host of small or derivitive sauces.
The basic recipe is equal amounts of fat and flour, and either milk or cream to thin, with a bit of salt to flavor. Just melt butter or heat oil in a pot. Note how much you use. add the same amount of measured flour, plus a bit of salt and stir into a thick paste. This is called a roux.
Let cook while stirring for about a minute over medium heat. Do'nt brown it. That's the basis for a different kind of sauce and will taste substantialy different. Add milk slowly while stirring until the roux thins into a rich sauce. From this point you can add parmesan cheese to make an Alfredo, or Add whipped egg-whites and spinace to make bake into a spinach soufle, or add some gruyere cheese and egg yolks to make a Hollaindaise, or add...
You get the idea.
If you thin the roux with animal broth, such as beef, veal, pork, chicken, or seafood, it is another of the mother suaces called a veloute. This is used for making various gravies, which is what you would want for your fake crab. You can then use it as is for a gravy or sauce to spoon over pasta or rice, or you can transform it into various soups and chowders, a bisque, or stew.
I know, I'm giving you a lot to swallow without much in the way of recipes. But that simple roux of flour and fat can be used to amke so much, even to thicken legume soups such as bean or split pea. Just thin the roux with liquid from the soup until a thick sauce is formed, and then stir into the soup to suspend the solid particles and keep them from settling. This is called binding the soup.
I use roux for so many things. It's even part of the ingredient list for cream puffs, i.e. butter, flour, heated to make the roux, then milk to begin the dough, followed by eggs, stirred into the paste. Then you have choux paste for making puffs, eclairs, protiferoles, etc.
Flour and fat, a wonderful thing
Seeeeya; Goodweed of the North