Not me ^
It's a whole lot of work to cast concrete. You need a form, a mixing tub or bucket, a screed and a strong back to carry the redimix at 80 lbs a bag.
Precast blocks come in 4" X 8" X 16" sizes. your step would need to be a module of 8" or 16" so that's 32" or 40" long X 16" or 24" wide. You may have to trim the pavers which may be 18" square....?
The answer to your question will only be as detailed and specific as the question is detailed and specific. Good questions also include a sketch or a photo that illustrates your issue. (:< D)