Place half of the russet potatoes in a large pot, cover with water, and bring to a boil.
Cook for 15–20 minutes until fork-tender, then drain and set aside.
In the same pot, cook ground turkey with onion and carrot until the meat is browned.
Stir in garlic and tomato paste, cooking for another couple of minutes until fragrant.
Add the remaining potatoes, chicken broth, Worcestershire sauce, rosemary, thyme, and bay leaves.
Bring to a boil, then reduce heat and simmer for 15–20 minutes.
While it simmers, mash the cooked potatoes and mix with the rest of the broth, butter, and Greek yogurt.
Stir the mashed potatoes into the soup.
When the vegetables are tender, add shredded cheddar, frozen peas, and salt and pepper to taste.
Heat through, then divide among bowls and top with parsley or more cheddar before serving.