I made a special effort and prepared a little broth with eggs poached in bain-marie, together with vetchlings; to which I added an accompaniment of croquettes of soft bread and a few salt pilchards minced together with herbs and raisins; and, to complete the meal, chicory roots, boiled with cooked must and vinegar. The whole I sprinkled with a pinch of cinnamon; the precious spice of the wealthy would surprise the palates and refresh the spirits.
'Vetchling' is "a plant or species of the genus Lathyrus; the genus itself" (OED). This genus includes the sweet pea.
I'm not sure what 'must' is in this context; possible contenders (again from the OED) include "the juice of freshly pressed grapes before or during fermentation into wine" and "any of several varieties of apple used chiefly for making cider".
I didn't know what (a) bain-marie is either, but I imagine that most of the readers of this blog will do.