Preheat the oven to 450 degrees F.
In a bowl, whisk together the pomegranate molasses and apple cider.
Place the pork in a roasting pan. Add the onions around it. If desired, you can cut slits into the pork roast and place the garlic slices inside! Otherwise, just add the garlic to the pan with hte onions.
Brush the pork all over the with pomegranate cider mixture, then pour the rest on top. Season with the salt and pepper.
Roast the pork for 20 minutes. Reduce the heat to 350 degrees F and roast for 45 minutes more, or until the internal temperature reaches 145 degrees F. It is SO important to use a meat thermometer here - this way, the pork can stay moist!
Remove the pork from the roasting pan and place it on the cutting board. Let the pork sit at room temperature for 20 minutes before serving.
In the meantime, place the roasting pan (leave the onions in it) over medium-low heat. Stir in the stock and cream and bring the mixture to a simmer, whisking constantly. Cook for 2 to 3 minutes until it’s slightly thickened. This pan sauce creates a delicious optional gravy.
Slice the pork roast and serve it with a sprinkling of pomegranate arils, the brussels, smashed potatoes and pan sauce.