Grilled Mackerel with Choûcroute, Bacon and Mustard Sauce from Cooks Country: Modern British Rural Cooking by Matt Tebbutt

Ingredients

• salt and pepper
• 1 banana shallot, peeled and finely chopped
• olive oil
• 1 tsp Dijon mustard
• 1 tbsp white wine vinegar
• 100 g pancetta or smoked bacon, diced
• 4 mackerel, left whole, gutted, heads removed, fins off, rinsed
• 100 ml double cream
• lemon juice
• 2 bay leaves
• 25 g unsalted butter
• 1 tsp coarse-grain mustard
• a few springs of fresh thyme
• 1 tbsp finely chopped fresh parsley
• 1 garlic clove, peeled and crushed
• 1 tbsp duck fat
• 1 bottle lager
• 125 ml white wine
• 500 g choûcroute
• a few juniper berries