Doneness

Testing the temperature with a candy thermometer is the most accurate way to determine the doneness of a syrup.

Source: wiktionary

Unlike meat cookery, in which doneness is specified by customer order and determined by temperature, ...

Source: wiktionary

In this section we look at how to test doneness of baked goods using three methods: observation, touch tests, and internal temperature.

Source: wiktionary

You can use a metaphor as a loose form of doneness testing. In one workshop, we used a bull's-eye. I created a poster with a bull's-eye showing concentric circles with the label "100%" in the center.

Source: wiktionary