To make the Garlic Butter Sauce, combine the butter and oil in a microwave proof bowl, then heat gently in the microwave to soften the butter, but ensure it doesn't fully melt. Whilst the mixture is still warm, stir in the miso paste, lemon juice, chopped garlic, parsley, salt and pepper and leave in a warm place to ensure the butter doesn’t set.
To make the Salsa Verde place all the ingredients in a food blender and blitz until you have a smooth, vibrant green sauce.
Place the chicken thighs, drumsticks and cauliflower pieces (including the leaves) in a large bowl. Pour the warm garlic butter over the ingredients and use your hands to mix everything together, ensuring each piece of chicken and cauliflower is smothered in the butter.
Place the marinated chicken and cauliflower in a deep-sided oven tray and bake in the oven for around 40 minutes, until the chicken is cooked. Make sure to turn the chicken and cauliflower every 10 minutes. To serve, spoon the salsa verde over the baked dish and serve with crusty bread and a crisp salad.