Ate nothing around the end of June, then ate a lot (7)
I believe the answer is:
feasted
'ate a lot' is the definition.
(to feast is to eat large quantities)
'ate nothing around the end of june' is the wordplay.
'ate nothing' becomes 'fasted' (to fast is to refrain from eating food).
'around' is an insertion indicator.
'the end of' indicates one should take the final letters.
The last letter of 'june' is 'e'.
'fasted' placed around 'e' is 'FEASTED'.
'then' acts as a link.
(Other definitions for feasted that I've seen before include "Ate lavishly" , "Ate high off the hog" , "Had a lot to eat" , "Banqueted" .)