"Soul! Soul! For a Soul Cake!
Pray you, good mistress, a Soul Cake!"
Soul Cakes, which are supposed to be handed out and eaten on November 2nd, the Feast of the Holy Souls, are also supposed to be made tomorrow, the 31st of October; but I am reasonably sure that your day will be spent putting in last minute touches to costumes and making sure there is enough swag to satisfy the ghoulies and ghosties and long-leggedy beasties (the accompanying parents) who will show up at your door, leaving little time for anything else.
So either make them today, or use this as a reminder to have the ingredients ready, in case you have time on your hands tomorrow.
There is quite a bit of information out there, some of it not worth the mentioning. Most of the good sources say that this was a time when bread was bought or made, and doled out to those who would pray for the family's dead. Sometimes it was a triangular cake, or a seed-cake, or a cake containing fruit or made with oatmeal. Whatever the ingredients, there should be a heap of them standing by, ready to give each visitor to the house.
Make one cake for each of your deceased relatives, and a few (or a lot) more for those who have nobody to pray for them.
And remember, the person who eats the soul cake is required to pray for a holy soul in Purgatory, even if it is only "(Name), God have your soul, bones and all."
To start with, Fisheaters has a great overview of "Hallowtide": "31 October and 1 and 2 November are called, colloquially (not officially), "Hallowtide" or the "Days of the Dead" because on these days we pray for or remember those who've left this world..." and a recipe for soul cakes in the shape of doughnuts. Oh, and it explains why All Hallows Eve has nothing to do with Irish pagan harvest festivals.
Historical Foods uses a bit of white wine vinegar to balance the sweetness of the sugar in their recipe for Souling Cakes, which is more like a shortbread cookie in shape and texture. The page has photos of the steps used. (It is based on British measurements, so I have listed the ingredients below):
3 cups plus 1 tablespoon of sifted flour
3/4 cup of sugar
3/4 cup of butter
scant 1/2 teaspoon of ground cinnamon, nutmeg, and 'mixed spice' (pumpkin pie spice comes closest)
scant 1-1/2 teaspoon of white wine vinegar
1 egg = 1 egg, no matter where you are, unless you are talking ostrich eggs.
Roll out dough to 1/4 inch.
Oven: 200 degrees C = 400 degrees F, which seems to be more a hot oven, rather than a moderate oven. Keep a watch on your cakes and lower the temperature to 375F if needed.
Catholic Culture has a yeast bread recipe, and says that originally the buns were "shaped like men and women, with raisins or currants for eyes" (much like you would decorate gingerbread men).
Gode Cookery uses a recipe from 1604 which has this advantage: it uses ale and dry sack sherry (only 1/2 cup of each, so there is plenty left for the cook!)
Now, get to it! There are a lot of Holy Souls for whom to pray. Perhaps one day, of your charity, you will pray for The Widow as well.