Heat olive oil in a spacious skillet over medium-high flame. Sauté the minced garlic and chopped onion for a minute. Incorporate the finely chopped carrot, celery, thyme, and rosemary. Cook for about 3 minutes until the vegetables are tender and aromatic.
Increase the heat to high and add the ground lamb or beef, breaking it apart as it cooks, until it’s nicely browned. Mix in the flour thoroughly, then add the tomato paste, beef broth, red wine, crumbled bouillon cube, Worcestershire sauce, and bay leaves. Stir the mixture well.
Bring to a gentle simmer, then reduce the heat to medium, allowing it to simmer for about 30 minutes. Stir occasionally until it thickens into a rich, hearty gravy (Note 1). Season with salt and pepper to taste. Transfer the filling into a 1.5-liter / 1.5-quart pie dish. Stir in the frozen peas. Cover and refrigerate for 1-2 hours or overnight for best results (Note 2).