Heat a large nonstick skillet, over medium heat and add the oil and butter. Add the onion and carrots and cook about 6 minutes or until the carrots have softened and are lightly browned.
Add garlic and cook another 30 seconds, until bloomed and fragrant.
Add rice and cook, stir until coated.
Add water, chicken stock, cream, ¼ teaspoon salt, ¼ teaspoon ground black pepper. Bring the rice mixture to a simmer and turn heat to low.
Cover and cook, stirring often, for 20-25 minutes or until most of the liquid is absorbed. The rice should be just tender.
Add the turkey, water chestnuts, Parmesan cheese, lemon juice, Worcestershire Sauce, tarragon and peas. Cook uncovered, stirring often, for 2 minutes.
Pour the turkey/rice mixture into the prepared casserole dish, sprinkle with the cracker topping and bake at 375°F until bubbly and the top is golden brown, about 20-25 minutes.
Transfer to a cooling rack and cool 5-10 minutes before serving.