Pat the chicken thighs dry with paper towels and season generously with salt and pepper. Heat a skillet over medium-high heat with a tablespoon of oil until shimmering. Sear the chicken pieces until golden brown on both sides, about 4-5 minutes per side, then transfer them to the slow cooker.
In the same skillet, add sliced onions and cook until translucent and fragrant, about 5 minutes. Add minced garlic and cook for another 30 seconds until fragrant, stirring constantly.
Pour in the chicken broth and scrape up any browned bits from the pan to build flavor. Stir in smoked paprika and tomato paste, mixing well to combine.
Pour this aromatic mixture over the chicken in the slow cooker. Add sliced bell peppers around the chicken for sweetness and color.
Cover the slow cooker with the lid and cook on low for 6 hours, until the chicken is tender and falling apart, and the sauce is deep and fragrant.
Once cooked, open the lid and stir in sour cream or coconut cream to add richness and tang. Adjust seasoning with additional salt or pepper if needed.
Let the dish rest uncovered for 10 minutes to allow flavors to meld. Serve hot over noodles, rice, or crusty bread, garnished with chopped parsley if desired.
