Update: my grandma's recipe card says 'bake until done' and a test kitchen in Boston says that's 350 for 32 minutes
I found this out last week when I called King Arthur's baker's hotline about my grandma's pound cake recipe that just says 'bake until done.' The person on the phone told me they tested the same vague wording from old church cookbooks and found most of them land between 325 and 375 for 30 to 35 minutes in a modern oven. Now I'm stuck arguing with myself: do I trust the old card and my gut, or do I write real numbers on it and lose the mystery? Curious if anyone else has updated a family recipe with real temps or if that feels like cheating.
What if the real question is whether your oven even runs true to temp? My mom's old wall oven ran about 25 degrees hot, so her "bake until done" cakes would have come out wrong in any modern recipe with real numbers. The card worked because she knew her oven, not because the recipe was magic. Writing down 350 for 32 might actually make it worse if your setup doesn't match the test kitchen's. Maybe write the number but add a note about what "done" looks like, the smell, the spring back, the toothpick. That way you keep the gut part and the number part both.