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Chutes‐and‐pools are hybrid bedforms that occur in upper‐flow‐regime conditions, populating the stability field between antidunes and cyclic steps. Chutes‐and‐pools consist of a superimposition of a train of antidunes on a longer‐wavelength cyclic‐step instability. The presence of a hydraulic jump is more persistent in chutes‐and‐pools than the bores occasionally seen on breaking‐wave antidunes, yet not permanent as over cyclic‐step bedforms. The nature of chute‐and‐pool structures preserved in the depositional record is controlled largely by aggradation rate. This paper documents chute‐and‐pool structures generated beneath highly aggradational sediment density‐flows at the subaqueous toe‐of‐slope of a Pleistocene carbonate wedge. Quarry exposures enable the morphodynamic reconstruction of the sediment‐bed configuration that produced the identified structures. Wave‐breaking on growing antidunes occurred without the destruction of the antidune, which deviates from observations in low‐aggradation subaerial open‐channel flows. The antidune build‐up was followed by hydraulic jump controlled deposition in the antidune trough. Two‐dimensional depth‐resolved numerical simulations have been used to validate this process interpretation. The term aggradational chutes‐and‐pools is proposed for these bedforms, associated with the formation of build‐and‐fill structures consisting of interstratified convex lenses (in‐phase wave regime) and concave lenses (hydraulic jump regime). Such structures contrast with the scour‐and‐fill structures produced by low‐aggradation chutes‐and‐pools frequently described from subaerial open‐channel‐flow deposits. This study demonstrates a potential difference in flow behaviour between open‐channel flows and density flows in the supercritical regime. [ABSTRACT FROM AUTHOR]