Rocket leaves now starter for lunch, and swell cakes provided (4-3)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

definition: the time at which a "Rocket leaves" starting letter of L-[unch], and TOFF=slang for an upper-class person="swell"; all around ("cakes") IF="provided" 'cake' as a verb meaning to cover, to coat e.g. 'caked in mud'