Melt the butter in a large pot over medium heat.
Add the chicken and cook for 5 to 6 minutes until lightly browned. Transfer to a plate.
Add the onion and cook for 3 to 4 minutes until softened, then stir in the garlic and cook for 30 seconds.
Sprinkle the flour over the onion mixture and cook for 1 minute, stirring constantly.
Gradually whisk in the chicken broth until smooth.
Stir in the corn, thyme, paprika, salt, and black pepper. Bring the soup to a gentle boil.
Return the chicken to the pot, reduce the heat, and simmer for 10 minutes until the chicken is cooked through.
Stir in the milk and heavy cream. Simmer gently for 3 to 5 minutes without letting the soup boil.
Taste and adjust the seasoning if needed.
Garnish with the green onions and fresh parsley before serving.