The term custard is derived from the French word croustade, meaning an uncovered pastry case (meant to be filled with a cooked milk and egg mixture). Therefore, the name for the case is actually now what we use to refer to the firm, thick filling. Interestingly, custards in Asia are traditionally made without milk; instead, water and sometimes oil are combined with eggs to make the custard.
Almonds in a Pie:Make thick milk of almond kernels. Make a shell of dough, pour the milk into it and cover the top with the same dough. Salt it, and bake it in a hot oven.
Notice that no eggs are used in this custard recipe, just almond milk and salt cooked in a pastry case. This must have been a recipe used on fast days when no eggs, dairy, butter, meat etc. were allowed to be consumed.
A set of recipes from the very late Medieval period/early classical period in the 16th century, Livre fort excellent de Cuisine (The Most Excellent Book of Cookery) has custard recipes for herb custard, custards served with roulade of venison, and tartlets.
By the 17th century, custards flavored with almonds, orange-flower water, orange, spices, and rice were quite popular. Here is a recipe from Gervase Markham's 1615 publication, The English Housewife (London):
Modern Recipe Adaptation: White Custards
- Whites of 6 Large Eggs
- 1/2 Cup Granulated Sugar, Divided
- 3 Cups Whole Milk
- 1 Tablespoon Vanilla Extract
- Heat oven to 350º F.
- In a large bowl, whisk together the egg whites and about half the sugar. Set aside.
- In a three-quart saucepan, whisk together the milk and the remaining sugar (the addition of the sugar to the milk will help prevent the milk from scorching). Set over medium heat and bring just to the boil and then immediately remove from the heat.
- Temper the eggs into the milk by ladling about 1 cup of the milk mixture into the eggs and whisk together. Then add the egg mixture into the saucepan with the milk. Whisk together.
- Add the vanilla extract and whisk.
- Place six custard ramekins in a large (10" x 15") rectangular casserole dish. Pour the custard evenly into into the ramekins. Pour boiling water into the casserole dish until it reaches a level half-way up the ramekins. Do not cover.
- Bake for 30 minutes, or until the custard is firm and jiggles just slightly when shaken.
References in Addition to Primary Sources Noted in Post