Season the shrimp and scallops on both sides with salt and pepper. Heat some oil in a large skillet over medium-high heat.
Cook the scallops for 2-3 minutes on each side, then remove them from the skillet. Add some butter and shallots to the skillet and cook for 1 minute.
Stir in the spinach and red crushed pepper, season with salt and pepper. Cover and cook for 1-2 minutes.
Stir in the fresh garlic and cook until fragrant. Add the heavy cream and parmesan cheese. Once the sauce thickens slightly, add the shrimp and cover. Cook for 1-2 minutes or until the shrimp are fully cooked through.
Place the scallops back into the skillet and cook for an additional 10-20 seconds. Check for seasoning and enjoy.
