Trim any excess fat from the chicken thighs and pat them dry with paper towels—this helps them brown better and prevents the sauce from becoming greasy. In a small bowl, whisk together the dijon mustard, honey, chicken broth, and coconut milk until smooth and well combined. In a separate small bowl, mix the paprika, salt, garlic powder, and black pepper. Set both mixtures aside. I like to prepare these components while the slow cooker is preheating because it keeps everything moving smoothly.

Place the arrowroot powder in a bowl or large zip-top bag. Working in batches if needed, coat each chicken thigh thoroughly with the arrowroot powder—this will help thicken the sauce as it cooks. Pour the mustard-honey sauce mixture into your slow cooker, then arrange the coated chicken thighs in a single layer, skin-side up if possible. Flip each piece to coat both sides with the sauce, ensuring the chicken is mostly submerged or well-coated.

Cover the slow cooker and cook on low for 6 hours. The chicken should be very tender and easily pull apart with a fork, and the sauce should have thickened noticeably from the arrowroot powder. I find that checking at the 5.5-hour mark helps ensure the chicken doesn't become overdone if your slow cooker runs hot. The sauce will bubble gently around the edges and develop a rich, caramelized appearance.