Melt butter in a Dutch oven over medium heat. Add onion, and sauté 4 minutes or until tender. Add potatoes, and cook 4 minutes. Add scallops, and cook 2 minutes. Stir in whipping cream. Cover and reduce heat; simmer 20 minutes.
Stir in Pernod, thyme, salt, and pepper. Cover and simmer an additional 10 minutes. Garnish, if desired.