Wash and dry the chicken and cut into 4 pieces. Rub thoroughly with crushed garlic.
Heat 50 g butter over medium-high heat. Add 65 g diced bacon and cook for 2-3 minutes until it releases fat. Add the 2 diced onions and cook for 3-4 minutes until softened. Add the 4 chicken pieces and brown for 8-10 minutes, turning occasionally, until golden on all sides. Deglaze the pan by pouring in 1 glass of white wine and scraping up any browned bits from the bottom.
Add 125 g sliced mushrooms, 2 bay leaves, and the 8-herb frozen mixture to the pan. Season with salt and freshly ground pepper. Reduce heat to low, cover, and simmer gently for 30 minutes until the chicken is cooked through (internal temperature 74°C / 165°F).
Transfer the chicken to a warmed serving plate and drizzle with 20 ml kirsch. Cover with foil to keep warm. Simmer the remaining sauce over medium heat for 2-3 minutes to reduce slightly, then season to taste with salt and pepper. Pour the sauce over the chicken.