250 g (8 oz) chicken breasts, cut into thin strips
175 g (6 oz) chestnut mushrooms, thickly sliced or quartered
400 ml (14 fl oz) crème fraîche
1 tablespoon Dijon mustard
4 tablespoons wholemeal breadcrumbs
4 tablespoons grated Parmesan cheese
watercress salad, to serve
Cook the pasta in a large saucepan of lightly salted boiling water for 5 minutes. Add the broccoli and cook for a further 5 minutes.
Meanwhile, heat the oil in a large heavy-based frying pan and cook the chicken over a high heat for 5 minutes. Add the mushrooms and cook for a further 3–4 minutes until both are golden and cooked. Add the crème fraîche and Dijon mustard and heat and stir for 1 minute until loosened and mixed together well.
Drain the pasta and broccoli well, toss into the frying pan and stir. Transfer to a large gratin dish, scatter with the breadcrumbs and Parmesan and cook under a preheated hot grill for 2–3 minutes until golden and bubbling.