I took home economics in middle school and nearly failed it.

I hated the sewing machine’s jumping needle, every seam coming out as if a path beaten through the jungle. But it was my cupcakes that most threatened my otherwise nice report card.

Mixing bowls and spoons, flour going everywhere, we were charged with the production of a dozen perfectly iced cupcakes. A dozen, we learned, meant thirteen, which only complicated the matter.

I recall the moment we girls, no boys, lined up at the kitchen island, our specimens on a platter. The teacher came around with her very sharp knife. Not even bothering to remove the paper baking cup, she sliced one of mine in half and found air tunnels running throughout the chocolate cake. Never mind the taste, my cupcakes were a failure.

This petty humiliation turned out to be a valuable writing lesson.

I think of those cupcakes now when I ask myself: when is a work done?

Some writers say that it’s when one can no longer find anything in need of improvement. For me, that’s an unworkable standard, as I can fiddle forever with a comma. A better sign, I think, certainly a good sign, and maybe even the whole sign, is when I can slice the work at any point, over and over and over, read the passage I’ve selected, and not find any dead air, just cake.