Turn Instant Pot on Sauté mode. Heat the ghee in pot, then add onion, carrots, and celery. Cook, stirring occasionally, until onions are softened, about 5 minutes. Add garlic and cook, stirring constantly, until fragrant, about 30 seconds to 1 minute. Add chicken broth, chicken, salt, freshly cracked black pepper, oregano, and bay leaf. Secure lid with valve in Sealing position and cook on Manual High Pressure for 10 minutes. Quick Release.

Meanwhile, in a high-speed blender, process coconut milk and cashews until very, very smooth.

When Instant Pot is finished cooking and pressure is released, stir in coconut-cashew mixture and cauliflower rice. Turn Instant Pot on Sauté mode and cook, stirring occasionally, until cauliflower rice is cooked through. Add pinch of turmeric for color, if desired. Season with additional salt to taste. Ladle into serving bowls and top with fresh chives, if desired.