For the monkfish: Preheat oven to 400 degrees F. Heat 2 tablespoons of olive oil in a large saute pan over medium-high heat. Season the monkfish with salt and pepper to taste. Sear on both sides until lightly golden brown. Place the fish in a small roasting pan and roast in the oven for 12 to 15 minutes.
For the potatoes: Preheat oven to 400 degrees. Toss potatoes in olive oil in season with salt and pepper to taste. Roast for 10 to 15 minutes, until just cooked through and lightly golden brown. .
For the sausage: Preheat grill or grill pan. Grill the sausage until golden brown and cooked through. Let rest and cut into 1/2-inch slices.
For the clam broth: Heat oil in a medium saucepan over medium heat. Add the onions and cook until soft. Add the garlic and cook for 2 minutes. Increase the heat to high, add wine and cook until reduced. Add broth and bring to a boil. Add clams, cover the pot and cook until the clams open, remove the clams with a slotted spoon to a bowl. Cook the broth until reduced by half. Add the tomatoes and cook for 2 minutes. Whisk in the butter, add the scallions and season with salt and pepper to taste.
Assemble: Cut the roasted monkfish into 4 pieces. Place a small amount of spinach in each bowl. Place a piece of monkfish on top of spinach and place 3 potatoes, 3 pieces of merguez and 3 clams around the edge. Ladle broth over and garnish with fresh parsley.