In a medium saucepan, combine the rinsed wild rice with 4 cups of the chicken broth. Bring to a boil over high heat, reduce the heat to low, cover, and let it simmer for about 45-50 minutes until the rice is tender and the grains have burst open. Drain any excess liquid and set aside.

In a large pot or Dutch oven, heat the olive oil over medium heat. Add the chopped onion, carrots, and celery. Sauté, stirring occasionally, for about 5-7 minutes, or until softened and the onion becomes translucent.

Add the sliced cremini mushrooms, cooking for another 5-7 minutes until tender. Then, add the minced garlic, dried thyme, sage, rosemary, and red pepper flakes (if using). Stir constantly for about a minute until fragrant.

Pour the remaining 4 cups of chicken broth into the pot with the sautéed vegetables. Stir in the wild rice and the shredded chicken. Bring to a gentle simmer over medium heat, then reduce to low, cover, and simmer for at least 30 minutes. Stir occasionally to blend the flavors.

Gently stir in the heavy cream (or coconut milk) and dry sherry (if using). Add the chopped parsley and season with salt and pepper to taste. Warm through carefully without boiling after adding the cream.

Ladle the soup into bowls, garnishing with toasted pecans or walnuts and grated Parmesan cheese if you like. Serve immediately and enjoy the comforting warmth!