Vanilla Ice Cream

A still-frozen ice cream from the era when the electric refrigerator's ice tray was the only freezer most homes had. No churning, no ice and salt — the whipped cream does all the work of keeping it soft.

• XX creamA designation for a heavy, whippable cream; the exact butterfat standard behind the mark is not something the recipe or its era's labelling makes clear. Modern heavy whipping cream (36-40 percent) is the sensible substitute.
• Single creamAmerican light cream or coffee cream, about 18-20 percent fat. Half-and-half is a little leaner but works; whole milk alone will freeze grainy and hard.
• Confectioners' sugarFine sugar dissolves readily in an uncooked mixture like this one, which may be why it is specified rather than granulated. The small amount of cornstarch in modern powdered sugar is harmless here.
• The trayUse any shallow metal pan, with the divider removed if you are working in an ice tray; metal chills faster than glass or plastic and gives a finer texture.
• Freezing temperatureEarly refrigerator freezing compartments were considerably warmer than a modern freezer, which is likely why the instruction stops at "mushy." A modern freezer at 0F will take the mixture well past that, so check at 45 minutes and again every 20.
• Getting the texture rightThis is the hinge: fold the light cream in gently so the whipped cream keeps its air, and do not let the mixture separate before it sets. If it does firm up solid, beat it smooth once with a fork or a mixer and return it to the freezer.
• Yield and servingAbout a quart, or four to six small servings. Best eaten within a day; without churning or stabilizers it turns icy after that.