Preheat a small saucepot over medium-high heat with 1 turn of the pan of EVOO. Add the onion, garlic and season with salt and pepper. Cook them stirring frequently for about 3-4 minutes. Add the grainy mustard, hot sauce, chicken stock and cream.
Bring it up to a simmer and cook until thick, about 2-3 minutes. Turn the sauce off and reheat it when youre ready to serve.
Place the bread in the food processor and use the pulse button to break it up then let it rip and make fine breadcrumbs.
In a bowl, combine the mayonnaise, scallions, parsley, red bell pepper, salt and freshly ground black pepper. Gently run your fingers through the crab meat feeling for any shells or cartilage but try not to break up the meat too much while you do so. Add the cleaned crab meat to the mayonnaise mixture. Add a quarter of the fresh breadcrumbs and gently fold it over to combine. Place the remaining breadcrumbs on a plate and divide the crab mixture into 4 equal portions.
Transfer the 4 crab portions to the plate with the breadcrumbs. Coat each one in the breadcrumbs, gently pressing the breadcrumbs and forming 1 to 1 1/2-inch thick cakes. Preheat a medium size non-stick skillet over medium heat with 3 turns of the pan of EVOO, about 3 tablespoons, and the butter. Once the butter melts, add the crab cakes and brown and cook them for about 4 minutes on each side or until they are golden brown and heated through.
Divide the sauce between two plates, top with the crab cakes and serve.