Dice the 300 g chicken breasts. In a bowl, mix 4 tablespoons walnut oil with 1 tablespoon soy sauce, add 1 teaspoon curry, 1/4 teaspoon paprika, and salt to taste. Add the diced chicken and coat well. Refrigerate for 30 minutes.
While the chicken marinates, clean the 2 carrots and cut them into thin strips using a vegetable peeler.
Heat 2 tablespoons sesame oil in a large saucepan over medium heat. Add the carrot strips, season with salt and pepper, and cook for 2-3 minutes until slightly softened. Remove with a slotted spoon and set aside.
In the same saucepan, add the marinated chicken including all the marinade. Cook over medium heat for 5-7 minutes, stirring occasionally, until the chicken reaches an internal temperature of 74°C (165°F). Remove the chicken and set aside.
Pour 250 ml coconut milk into the saucepan and stir. Add 1 cup sour cream and stir until smooth.
Dissolve 2 teaspoons chicken broth concentrate in roughly a cup of warm water. Pour the broth into the saucepan. Season with curry and salt to taste.
Bring the sauce to a simmer over medium heat. If you want a thicker sauce, mix 2-3 teaspoons cornstarch with roughly 2-3 teaspoons cold water to make a slurry, then stir into the sauce. Simmer for 2 minutes until thickened.
Return the cooked chicken and carrots to the saucepan. Simmer over medium heat for 10 minutes to blend the flavors.