Preheat a large sauté pan over medium-high heat. Season the chicken with salt and pepper and toss to coat.
Add the ghee and heat until melted. Add the chicken and spread it out into an even layer. Cook, undisturbed, until golden brown, around 6 minutes. Flip and brown the other side, 6 more minutes. Reserve the fat in the pan and transfer the chicken to a bowl. Set aside.
Add the onions and season with a pinch of salt. Cook, stirring and scraping any brown bits off the bottom of the pan, until golden brown, around 6 minutes. Add the garlic and paprika and cook, stirring, 2 minutes. Add the chicken stock and scrape up any brown bits off the bottom of the pan. Return the browned chicken and add the tomatoes and red pepper. Bring to a simmer, reduce the heat to low, cover with a lid and cook until the chicken is tender, around 30 minutes.
In a small bowl, combine the arrowroot starch and water and stir to make a slurry. Add the slurry, coconut sour cream, and Dijon mustard to the pan and stir through. Cook until slightly thickened, around 4 minutes. Taste for seasoning and adjust with salt and pepper as desired.
Let cool 10 minutes before serving with your side dish of choice and garnishing with fresh parsley.