Posted: 5 January 2021
Preheat the oven to 190°C/375°F. Peel the potatoes and cut into cubes. Trim the green beans. Finley grate the cheese into a bowl and mix with the mayonnaise.
Place the potatoes in a pan of boiling water with a pinch of salt (optional) and cook for 8-10 minutes until tender.
Place the cod on squares of parchment paper in a small baking tin (this makes them easier to lift out later and dry well with kitchen paper. Season lightly with salt (optional) and freshly ground black pepper, then spread the Dijon mustard on top. Divide the cheese mixture between them and spread out gently with a knife.
Arrange the vines of cherry tomatoes around the cheesy cod and drizzle with the oil, then season them lightly with salt (optional) and freshly ground black pepper. Bake for 10-12 minutes until the cod is cooked through and flakes easily – check with a small sharp knife. The cherry tomatoes should be just lightly charred and just beginning to split.
Place the green beans in a steamer and cook for 3-4 minutes until just tender but still with a little bite.
Meanwhile, drain the potatoes and return to the pan over a low heat and shake for a minute or two to dry out. Mash until smooth, then beat in the butter, milk and wholegrain mustard. Season with freshly ground black pepper.
Arrange the cheesy cod on plates with the cherry tomatoes and add the mustard mash and steamed green beans to serve.