Swanenhalse (from Holland)

A savoury éclair under a Dutch name: choux paste piped into an S, baked hollow, and filled with a salt-fish and pickle paste. The entry assumes you already know how to make and bake eclair batter, and gives no quantities at all, so treat it as a formula rather than a recipe.

• The hinge: bake the shells dryThe entry gives no oven guidance. By modern choux practice, start at 425F for about 15 minutes to get the lift, drop to 350F for another 15-20 until the shells are firm and coloured all over, then pierce each one and return it to a switched-off oven to dry the inside. A damp shell will go soft within minutes of being filled.
• Eclair batterStandard choux: 1 cup water, 1/2 cup butter, 1 cup flour, 4 eggs, and a pinch of salt makes roughly 12 to 18 shells of 3 to 4 inches. Since the filling is salty, leave out any sugar.
• SardellesSardellen is the German word for salt-cured anchovies, which reached English cookbooks in that form; they were sold as whole fish in brine, which is why the recipe tells you to bone and skin them. Anchovy fillets in oil or salt do the same work; rinse salt-packed ones and pat dry, and taste before adding anything else, as they carry most of the seasoning the filling needs.
• Dutch mustardNot the sharp yellow English style; the term usually points to a Dutch or German table mustard, often coarse-ground and less fierce, and in books of this period 'Dutch' sometimes stands for German. A Dutch or German table mustard, or a smooth Dijon cut with a little of the pickle brine, will sit close enough.
• The fillingMash the yolks of hard-boiled eggs with the pounded anchovy, finely chopped sour pickles and the mustard. Work in soft butter or cream cheese if it will not hold together; a stiff paste pipes into the shells, a wet one seeps through and softens them.
• Cream cheese garnishAt this period the term generally meant a fresh unripened curd cheese, closer to today's quark or fromage blanc than to block cream cheese. Pipe a small rosette on each shell shortly before serving.
• Yield and servingPerhaps a dozen to eighteen small pieces from the choux quantity above, enough for six to ten as an hors d'oeuvre with drinks. Fill within an hour of serving.