Do I have to rake the thin layer of mulch out of my flower bed before rototilling?

nope.. we call this soil conditioner... the organic content of the mulch will boost the organics in the soil.. it would be a good idea to roll a little fertilizer in there, too... just cheap garden fertilizer like 10-10-10 or 12-12-12 will do.Do I have to rake the thin layer of mulch out of my flower bed before rototilling?
No the mulch is good for the soil.Do I have to rake the thin layer of mulch out of my flower bed before rototilling?
No! If it is a thin layer as you say I would till it in the soil this helps the soil hold water and as the mulch decompses it will add fertility to you beds.
no don't remove it it will make the soil better