Preheat your slow cooker.
Season the chicken thighs generously with salt and pepper on all sides.
Heat 1 tablespoon (15 ml / 0.5 fl oz) of ghee in a large skillet over medium-high heat.
Place the chicken thighs skin-side down in a single layer and cook for 5 minutes until the skin is golden and crisp.
Flip and cook for another 3 minutes.
Remove the chicken and set aside.
Add the remaining 1 tablespoon (15 ml / 0.5 fl oz) of ghee to the skillet.
Add the chopped onion and cook for 5-8 minutes until softened and lightly browned.
Stir in the minced garlic and sliced peppers and cook for one minute until fragrant.
Pour in 1/2 cup (480 ml) of the chicken stock to deglaze the pan, scraping up any browned bits.
Stir in the marjoram, black pepper, 1 tablespoon (15 ml / 0.5 fl oz) of the paprika, and the chopped tomatoes.
Bring the mixture to a simmer.
Transfer the sauce mixture to the slow cooker. Nestle the browned chicken thighs into the sauce.
Cover and cook on low for 5 hours.
After 5 hours, gently remove the chicken from the slow cooker and set aside.
In a separate bowl, whisk the egg yolks with the remaining 1/2 cup (480 ml) of chicken stock. Slowly drizzle this mixture into the slow cooker, stirring constantly to prevent curdling.
Stir in the remaining 3 tablespoons (45 ml / 1.5 fl oz) of paprika and the sour cream until well combined. Return the chicken to the slow cooker, cover, and cook on low for another hour.
Garnish with fresh parsley before serving.
Taste and adjust seasoning if needed.
Serve hot with cauliflower rice or shirataki rice.
Don't skip searing the chicken! This step creates a deep, rich flavor base for the entire dish that you can't get from the slow cooker alone.