Heat olive oil in a large pot over medium heat. Add the diced onion, and sauté for about 3 minutes until softened.
Stir in the minced garlic, diced carrots, and diced celery. Cook for an additional 5 minutes, stirring occasionally.
Add the chicken pieces to the pot and cook until they're no longer pink, about 5-7 minutes.
Pour in the chicken broth, then add the frozen corn, heavy cream, dried thyme, salt, and pepper. Stir to combine.
Bring the soup to a gentle boil, then reduce the heat and let it simmer for about 15 minutes, stirring occasionally, until the chicken is cooked through and the soup is heated.
Taste and adjust seasonings if needed. If you prefer a thicker consistency, let it simmer a bit longer or use a ladle to puree a portion of the soup.
Serve hot, garnished with fresh parsley if desired.
Store any leftovers in the refrigerator for up to 3 days. Reheat gently on the stove before serving.