A sonic hydrogen jet discharging into a high enthalpy supersonic crossflow over a flat plate is numerically investigated using large eddy simulation. The incoming freestream has a Mach number of 2.4 and the hydrogen jet is injected into the flow with a jet to crossflow momentum flux ratio (J) of 5. The present study is carried out in OpenFOAM® software, an open-source computational fluid dynamics solver package. The rhoCentralFoam solver is modified to accommodate species transport and combustion and later coupled with Cantera 2.5.0 to take advantage of the species libraries from Cantera. The flame penetration from the present study shows excellent agreement with the experiment. The OH mass fraction is mainly concentrated on jet shear layer, near flat plate surface and at the upstream separation. The horseshoe vortex helps in the spanwise spread of the flame, while the interaction of freestream with horseshoe vortex promotes mass exchange between the vortex and downstream wake. The flame between jet and crossflow shear layer is intermittent, with localized auto ignition zones.