  We use Minkowski Functionals to explore the presence of non-Gaussian
signatures in simulated cosmic microwave background (CMB) maps. Precisely, we
analyse the non-Gaussianities produced from the angular power spectra emerging
from a class of inflationary models with a primordial step-like potential. This
class of models are able to perform the best-fit of the low-$\ell$ `features',
revealed first in the CMB angular power spectrum by the WMAP experiment and
then confirmed by the Planck collaboration maps. Indeed, such models generate
oscillatory features in the primordial power spectrum of scalar perturbations,
that are then imprinted in the large scales of the CMB field. Interestingly, we
discover Gaussian deviations in the CMB maps simulated from the power spectra
produced by these models, as compared with Gaussian $\Lambda$CDM maps.
Moreover, we also show that the kind and level of the non-Gaussianities
produced in these simulated CMB maps are compatible with that found in the four
foreground-cleaned Planck maps. Our results indicate that inflationary models
with a step-like potential are not only able to improve the best-fit respect to
the $\Lambda$CDM model accounting well for the `features' observed in the CMB
angular power spectrum, but also suggesting a possible origin for certain
non-Gaussian signatures observed in the Planck data.
