A method of upgrading bitumen in a plant comprising a diluent recovery unit that processes diluted bitumen and outputs atmospheric topped bitumen (ATB), a vacuum distillation unit which processes ATB and outputs vacuum topped bitumen (VTB), and at least one fluid coker unit which processes VTB and outputs a tar pot bottom stream comprising heavy heavy gas oil is provided comprising the step of processing the tar pot bottom stream in a catalytic hydrocracking unit comprising an ebullated bed reactor to produce naphtha, light gas oil, and heavy gas oil.