A Scotsman's Shepherd Pie

Name: A Scotsman's Shepherd Pie
Prep time: 45 min
Cook time: 25 min
Total time: 1 h 10 min
Cuisine: European, British
Ingredients: 5 cups mashed, boiled potatoes; 0.5 cup sour cream; 2 ounces cream cheese; 2 tablespoons butter, softened, divided; 1 egg yolk; 0.5 teaspoon kosher salt; 0.5 teaspoon freshly ground black pepper; 1.5 teaspoons olive oil; 1 pound ground lamb; 1 pinch salt and ground black pepper to taste; 1 (16 ounce) can stewed tomatoes with juice, chopped; 1 small onion, chopped; 1 small carrot, peeled and chopped; 0.5 cup peas; 1 cup Irish stout beer (such as Guinness®); 1 cube beef bouillon; 1 tablespoon all-purpose flour; 1 tablespoon Worcestershire sauce; 0.75 cup shredded sharp Cheddar cheese; 2 teaspoons chopped fresh parsley; 2 teaspoons smoked paprika