Heat oil in a large skillet over medium high heat, then add onion and garlic.
Cook onion and garlic for 1 minute, stirring so as not to burn.
Add carrots, celery, oregano, sage, thyme and rosemary, and cook for 3 minutes. Then turn heat up to high.
Add lamb and use a wooden spoon to break it up as you cook it. Cook until browned.
Once lamb is browned, and broken up, add flour and stir it in.
Add tomato paste, broth, bouillon cube, Worcestershire sauce, and salt and pepper. Stir well.
When mixture starts bubbling, turn heat down to medium, and simmer for 30 minutes, stirring from time to time. Continue to cook until the sauce has reduced to the thickness you desire.
Taste, and adjust seasonings to your preference.
Pour mixture into a 2 qt baking dish.
Add peas and stir to combine.
Put mixture into refrigerator and preheat oven to 350 degrees F.