Tweedsmuir creation: take one for nothing, I have it in white (7,6)

'tweedsmuir creation' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'take one for nothing i have it in white' is the wordplay.
I cannot quite understand how this works, but
'take' could be 'r' (recipe is latin for take - r is abbreviation) and 'r' is found within the answer.
'one' could be 'an' (I've seen this in other clues) and 'an' is found in the answer.
'i' could be 'a' and 'a' is present in the answer.
This explanation may well be incorrect...

Can you help me to learn more?