750g Vivaldi potatoes (choose evenly sized ones) 25g butter, plus extra for greasing 1 large or 2 medium shallots, finely sliced 1-2 garlic cloves, crushed 110g shredded ham hock 300ml double cream 200ml whole milk 1 tbsp wholegrain mustard (if you love it, add a bit more) 2 tsp thyme leaves
