We report observations of the optical counterpart of the long gamma-ray burst (LGRB) GRB 230812B, and its associated supernova (SN) SN 2023pel. The proximity ($z = 0.36$) and high energy ($E_{gamma, rm{iso}} sim 10^{53}$ erg) make it an important event to study as a probe of the connection between massive star core-collapse and relativistic jet formation. With a phenomenological power-law model for the optical afterglow, we find a late-time flattening consistent with the presence of an associated SN. SN 2023pel has an absolute peak $r$-band magnitude of $M_r = -19.46 pm 0.18$ mag (about as bright as SN 1998bw) and evolves on quicker timescales. Using a radioactive heating model, we derive a nickel mass powering the SN of $M_{rm{Ni}} = 0.38 pm 0.01$ $rm{M_odot}$, and a peak bolometric luminosity of $L_{rm{bol}} sim 1.3 times 10^{43}$ $rm{erg}$ $rm{s^{-1}}$. We confirm SN 2023pel’s classification as a broad-lined Type Ic SN with a spectrum taken 15.5 days after its peak in $r$ band, and derive a photospheric expansion velocity of $v_{rm{ph}} = 11,300 pm 1,600$ $rm{km}$ $rm{s^{-1}}$ at that phase. Extrapolating this velocity to the time of maximum light, we derive the ejecta mass $M_{rm{ej}} = 1.0 pm 0.6$ $rm{M_odot}$ and kinetic energy $E_{rm{KE}} = 1.3^{+3.3}{-1.2} times10^{51}$ $rm{erg}$. We find that GRB 230812B/SN 2023pel has SN properties that are mostly consistent with the overall GRB-SN population. The lack of correlations found in the GRB-SN population between SN brightness and $E{gamma, rm{iso}}$ for their associated GRBs, across a broad range of 7 orders of magnitude, provides further evidence that the central engine powering the relativistic ejecta is not coupled to the SN powering mechanism in GRB-SN systems.