In a large pot, heat the olive oil over medium heat. Add the chopped onion and minced garlic, sauté until the onion is translucent, about 3-4 minutes.
Add the minced beef to the pot, breaking it apart with a spoon. Cook until browned, around 5-7 minutes. Drain any excess fat if necessary.
Stir in the diced carrots and frozen peas, cooking for another 2-3 minutes until slightly tender.
Add the tomato paste, beef broth, Worcestershire sauce, thyme, salt, and pepper. Bring the mixture to a simmer, then reduce heat to low and cover partially.
In a separate bowl, whisk together the flour, baking powder, and salt.
Cut in the cold butter until the mixture resembles coarse crumbs. Stir in the milk gradually until a soft dough forms. If desired, mix in chopped parsley for added flavor.
Once the beef mixture is simmering, drop spoonfuls of dumpling batter over the surface. Cover the pot with a lid and let the dumplings steam on top of the beef mixture for about 15-20 minutes, until they are fluffy and cooked through.
After the dumplings are fully cooked, gently fluff them with a fork and mix them in with the beef stew.
Serve warm in bowls, garnished with additional parsley if desired.