Remarkably safe recipe for emergency exit (4,6)
I believe the answer is:
fire escape
'emergency exit' is the definition.
('fire escape' can be a synonym of 'emergency exit')
'remarkably safe recipe' is the wordplay.
'remarkably' is an anagram indicator (I've seen this in other clues).
'safe'+'recipe'='saferecipe'
'saferecipe' anagrammed gives 'FIRE-ESCAPE'.
'for' acts as a link.
(Other definitions for fire escape that I've seen before include "Evacuation staircase" , "rescue apparatus" , "steps outside" , "it could be a life-saver" , "Emergency way out" .)