Heat olive oil in a large pot over medium heat.

Add diced chicken, salt, and pepper, and cook until lightly browned. Remove and set aside.

In the same pot, add onion, garlic, carrots, and celery. Cook until softened and fragrant.

Sprinkle flour over the vegetables and stir well to coat.

Slowly pour in the chicken broth, stirring constantly to avoid lumps.

Add milk and dried herbs, then bring to a gentle simmer.

Return the cooked chicken to the pot and cook until the soup thickens slightly.

Stir in Greek yogurt until fully incorporated and creamy.

Add frozen peas and cook for a few more minutes until heated through.

Taste and adjust seasoning as needed before serving.