In summer, such a chance as we have of dining alfresco? (7)
I believe the answer is:
outside
'alfresco?' is the definition.
('outside' can be similar in meaning to 'alfresco')
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for outside that I've seen before include "having emerged from the tunnel?" , "Tedious (anag)" , "Exterior" , "Where smokers now often must go" , "In the fresh air?" .)