Boston Brown Bread Ice Cream

A fountain-trade formula, written in the shorthand of a professional manual: the base is assumed, and only the flavoring is spelled out. Two versions are given, a churned custard ice cream and a still-frozen whipped-cream one.

• The missing first recipe"The same rules as for the foregoing recipe" points to the brown-bread ice cream's predecessor in the book, almost certainly a plain vanilla ice cream base. Read it as: make a quart of vanilla ice cream base, stir in the crumbs, freeze as usual.
• Roasted and pulverizedThis is the hinge. Boston brown bread is moist and steamed; added straight it turns to paste. The original gives no temperature; in a modern oven, slice it thin and dry it in a low oven until hard and dark at the edges, cool it completely, then grind it fine. The roasting is what gives the flavor its toasted, almost coffee-like edge.
• Boston brown breadA steamed rye, cornmeal and wheat bread sweetened with molasses, traditionally cooked in a cylindrical tin. Canned versions are still sold in New England; homemade or canned both work, but the crumb must be dried thoroughly before grinding.
• QuantityEight ounces of crumb to a quart of base is a lot, though the original does not say whether the bread is weighed before or after roasting -- either way this is a pronounced, grainy ice cream rather than a hint of flavor. Half that gives a smoother result if you want the texture closer to modern ice cream.
• Double creamIn American usage of this period the term indicated a rich cream, generally well above ordinary table cream; modern heavy or whipping cream is the practical equivalent. British double cream, at around 48 percent butterfat, is richer than intended.
• The second methodWhipped cream, sweetened, flavored with rum and mixed with the crumbs. The text gives only the mixture, but a whipped-cream base of this kind was normally still-frozen -- packed in a mold rather than churned. The aerated cream and the alcohol keep it comparatively soft.
• RumJamaica rum meant a dark, heavily estered pot-still rum, not a light mixing rum. The recipe gives no quantity; use a restrained hand, since a large amount of alcohol will keep the mixture from setting firm.
• YieldThe original states no yield. A quart of base plus the crumbs makes somewhat more than a quart; the pint of whipped cream in the second method roughly doubles in volume. How many servings that gives depends entirely on portion size.