Valuable things Tessa's sorted out (6)
I believe the answer is:
assets
'valuable things' is the definition.
(I've seen this before)
'tessa's sorted out' is the wordplay.
'sorted out' indicates anagramming the letters.
'tessas' anagrammed gives 'ASSETS'.
(Other definitions for assets that I've seen before include "One's total goods" , "capital" , "Total value of possessions" , "Stance discouraging particular action" , "Valuable resources" .)