Preheat your oven to 400°F. Place the chopped potatoes in a pot, cover with water and add a pinch of salt. Bring to a boil and simmer for about 15 minutes until the potatoes are fork-tender. Drain and mash with 1 cup low-fat half and half, butter, and a pinch of salt and pepper.
Meanwhile, heat olive oil in a large skillet over medium-high heat. Add the chopped onion, carrots, celery, and minced garlic. Sauté for 8-10 minutes until the vegetables soften.
Add the ground turkey and cook until browned and broken into small pieces, about 10 minutes. Stir in the onion salt, garlic salt, dried oregano, and dried thyme.
Mix in the tomato paste, Worcestershire sauce, and all-purpose flour. Cook for an extra minute. Then, slowly pour in the chicken broth while stirring. Let the mixture simmer for about 5 minutes until the sauce thickens. Stir in the frozen peas.
Spread the turkey and vegetable mixture evenly into a greased 9x13-inch baking dish. Top with the mashed potatoes, smoothing with a spoon or fork to create a light topping.
Bake in the preheated oven for 25 minutes, until the top is lightly browned and the filling bubbles. Garnish with parsley.