Heat olive oil in a large soup pot over medium to medium-high heat. Saute onion, carrots, and celery until they begin to become tender and caramelize, about 10 minutes. Add garlic and saute for 1 minute. Season vegetables with a generous sprinkling of salt and pepper while cooking.

Stir in butter to melt; stir flour into the veggies and butter until evenly distributed and veggies are coated. Pour in broth and milk, stirring until well combined. Turn the heat up and bring the mixture to a simmer. Add thyme, salt, pepper, and turmeric. Stir in peas and corn. Stir in chicken to combine and allow to simmer, 10 to 15 minutes. Taste and adjust seasonings before serving.