Heat olive oil in a skillet over medium-high heat for about 2 minutes.
Add chopped onion and cook for about 5 minutes, stirring occasionally.
Add ground lamb and break it apart while cooking. Stir in parsley, thyme, rosemary, salt, and pepper. Cook until browned.
Stir in Worcestershire sauce and minced garlic.
Add flour and tomato paste, stirring well to combine.
Add beef broth, peas, carrots, and corn. Bring to a boil, then reduce heat and simmer for about 5 minutes. Set aside.
Preheat oven to 400°F.