Cook Chicken and Veggies: Heat olive oil in large 3 ½-4 quart skillet, brasier, or sauté pan over medium heat. Add carrots, onions, and diced chicken to skillet. Turn heat to medium-high and, stirring occasionally, cook until onions are translucent and chicken is cooked through (about 8-10 min). Add white wine and stir to deglaze pan. Add peas, salt, and pepper and stir to heat through. Turn heat down to medium.
While Chicken and Veggies and cooking, make Sauce: In medium saucepan over medium heat, melt ghee. Whisk in milk, cream, and bone broth. Add thyme, salt, pepper, and nutmeg and stir to combine. Whisk until steamy, but not simmering (about 3-6 minutes). Whisk in spelt flour until no lumps remain.
Put it together: Carefully pour sauce into skillet with Chicken and Veggies. Stir to evenly combine. Continue to heat, stirring frequently until bubbly and thick (about 5-7 minutes).