Set your slow cooker to high. Heat a large non-stick frying pan over medium-high heat. Add a splash of olive oil and brown the chicken pieces on both sides until golden, about 3-4 minutes per side. Work in batches to avoid overcrowding. Transfer browned chicken to the slow cooker.
In a bowl or jug, mix together the white wine, chicken stock, Dijon mustard, crushed garlic, and chopped herbs. Pour this mixture over the chicken in the slow cooker. Add the bay leaves.
Season generously with salt and freshly ground black pepper.
Cover and cook on high for 4 hours or on low for 8 hours, until the chicken is fall-off-the-bone tender.
Serve immediately with crusty bread, roasted potatoes, or your favourite side. Spoon the sauce generously over everything.