Reddish-white colour turning up in pasty? Outstanding! (7)

'outstanding' is the definition.
(thesaurus)

'reddish-white colour turning up in pasty?' is the wordplay.
'reddish white colour' becomes 'bay' (I can't justify this - if you can you should believe this answer much more).
'turning up' says the letters should be written backwards.
'in' means one lot of letters goes inside another.
'pasty?' becomes 'pale' ('pale' can be a synonym of 'pasty').
'bay' in reverse letter order is 'yab'.
'yab' inserted within 'pale' is 'PAYABLE'.

Can you help me to learn more?