  The SOSS mode of the NIRISS instrument is poised to be one of the workhorse
modes for exoplanet atmosphere observations with the newly launched James Webb
Space Telescope. One of the challenges of the SOSS mode, however, is the
physical overlap of the first two diffraction orders of the G700XD grism on the
detector. Recently, the ATOCA algorithm was developed and implemented as an
option in the official JWST pipeline, as a method to extract SOSS spectra by
decontaminating the detector -- that is, separating the first and second
orders. Here, we present APPLESOSS (A Producer of ProfiLEs for SOSS), which
generates the spatial profiles for each diffraction order upon which ATOCA
relies. We validate APPLESOSS using simulated SOSS time series observations of
WASP-52\,b, and compare it to ATOCA extractions using two other spatial
profiles (a best and worst case scenario on-sky), as well as a simple box
extraction performed without taking into account the order contamination. We
demonstrate that APPLESOSS profiles retain a high degree of fidelity to the
true underlying spatial profiles, and therefore yield accurate extracted
spectra. We further confirm that the effects of the order contamination for
relative measurements (e.g., exoplanet transmission or emission observations)
is small -- the transmission spectrum obtained from each of our four tests,
including the contaminated box extraction, is consistent at the $\sim$1$\sigma$
level with the atmosphere model input into our noiseless simulations. We
further confirm via a retrieval analysis that the atmosphere parameters
(metallicity and C/O) obtained from each transmission spectrum are consistent
with the true underlying values.
