Pale brown colour (7)
(Other definitions for beige that I've seen before include "Yellowish-brown" , "Shade of brown" , "Taupe" , "Light sandy fawn colour" , "Pale brown" .)
'pale brown colour' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for oatmeal that I've seen before include "Pale variegated brown colour" , "Porridge constituent" , "ground food!" , "It's boiled for porridge" , "Porridge ingredient" .)