The Old-School World War II Trick That Doubles Your Butter - Tasting Table

"Though this hack has been used by homemakers since the 1920s, an article published in 1943 instructed those looking to double up their butter to first cut a pound of butter into cubes and let it reach room temperature before adding an unflavored gelatin packet to evaporated milk, salt, and then mix the enhanced evaporated milk together with the butter."

"If you don't have evaporated milk on hand and are looking to feed a bigger crowd, churn any milk or cream into butter and whip in a mixer to have more bang for your proverbial buttered buck. Condensed milk is another good option that achieves very similar results. Use on potatoes or toast, but be warned: Once you start spreading this mixture onto homemade yeast rolls and warm stacks of pumpkin pancakes, you may be pleasantly surprised"

Evaporated milk can be whipped into butter to stretch quantity and create a smoother, spreadable product that can last about a month refrigerated. Typical ratio examples include about 8 ounces of evaporated milk per pound of butter, adjustable for desired thickness. A 1943-era preparation added an unflavored gelatin packet with evaporated milk and salt before blending with softened butter. Salt or honey can be incorporated for taste. When evaporated milk is unavailable, churning milk or cream into butter or using condensed milk produces similar volume-extending results suitable for spreading on potatoes, toast, rolls, and pancakes.

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