Roasted Sprout Gratin with Bacon-Cheese Sauce

Taken from the BBC Good Food website


800g Brussels sprouts
1 tbsp sunflower oil
85g bacon lardons
85g fresh breadcrumbs
25g butter
400ml milk
50g plain flour
2 tsp English mustard powder
100g Gruyère, grated
25g Parmesan, grated


  • Heat oven to 200C/180C fan/gas 6.
  • Halve any large sprouts and toss them with the oil and some seasoning in a roasting tin or ovenproof dish. Roast for 20 mins until the sprouts are tender and turning golden.
  • Meanwhile, put the bacon lardons in a cold frying pan and place over a medium-low heat. Gently fry the lardons so the fat melts out into the pan as they crisp. When golden brown and crisp, remove from the pan with a slotted spoon.
  • Add the breadcrumbs and crisp up in the bacon fat until golden and crunchy. Remove from the pan to cool, then clean the pan.
  • Melt the butter in the pan with 2 tbsp of the milk, then stir in the flour and mustard powder for 2 mins to make a paste.
  • Gradually whisk in remaining milk, until you have a smooth sauce. Use a spoon again to stir and cook until the sauce comes to the boil and thickens.
  • Turn off the heat and stir in the cheese until melted. Taste and season.
  • Tip the sprouts into a baking dish, scatter with the crisp bacon lardons, then spoon over the sauce and scatter with the crispy crumbs.
  • Can be cooled, covered and chilled for up to 48 hrs before baking. Bake gratin for 10 mins (or 20 mins from chilled) at 200C/180C fan/gas 6 until piping hot and bubbling.