break nested object apart into individual polygons

I have basically a sketch which consists of multiple nested(innerlying), not overlapping polygons:

I would like to get polygons for each alternating region, something which I can achieve with the combine command (polygons filled black):

However, now everything is one object, how can I break that down into (in this case 3) individual polygons? I know that I can achieve what I want by subtracting each region from each other (see below, only outer polygon selected here), however I was wondering if there is a solution which can do everything in one step.