Cooking sausage perhaps of unknown length, stopping the one who'd measure it? (7)

'cooking sausage' is the definition.
The definition suggests a singular noun which matches the answer.

'of unknown length stopping the one who'd measure it?' is the wordplay.
I cannot really see how this works, but
'unknown' could be 'z' (algebra) and 'z' is present in the answer.
'length' could be 'r' (r is a kind of length) and 'r' is found within the answer.
'one' could be 'i' (Roman numeral) and 'i' is found within the answer.
'measure' could be 's' (S is an example) and 's' is located in the answer.
'it?' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is present in the answer.
This explanation may well be incorrect...

'perhaps' is the link.

Can you help me to learn more?