Strangely, dog in street ultimately ate dull food (6)
I believe the answer is:
stodge
'dull food' is the definition.
(I've seen this before)
'strangely dog in street ultimately ate' is the wordplay.
'strangely' is an anagram indicator.
'in' is an insertion indicator.
'street' becomes 'st'.
'ultimately' indicates one should take the final letters.
The last letter of 'ate' is 'e'.
'dog' with letters rearranged gives 'odg'.
'st'+'e'='ste'
'odg' placed into 'ste' is 'STODGE'.
(Other definitions for stodge that I've seen before include "Heavy and indigestible food" , "Heavy food (colloq.)" , "Heavy, often starchy, food" , "Food that's hard to digest" , "treacle pudding?" .)