Heat olive oil in a large pot or Dutch oven over medium heat.
Add the diced onion, carrots, and celery, cooking until softened, about 5 minutes.
Stir in the minced garlic and cook for another minute until fragrant.
Add the diced chicken to the pot, cooking until lightly browned, about 5-7 minutes.
Pour in the chicken broth, and add the frozen corn kernels, diced potatoes, dried thyme, salt, and pepper.
Bring the mixture to a boil, then reduce heat and let simmer for 20 minutes, until the potatoes are tender and chicken is cooked through.
If desired, use a blender to puree a portion of the chowder for a creamier texture. Otherwise, leave it chunky.
Stir in the heavy cream and adjust seasoning as necessary. Heat for an additional 5 minutes.
Serve hot, garnished with fresh parsley.