LEEK AND BROCCOLI PENNE WITH CRUNCHY TOPPING

1 leek, chopped into large chunks
1 head broccoli, broken into florets
1tsp butter
0.5 pint cheese sauce (either white sauce with cheddar melted into it, or ready-made)
250g fresh penne
Two slices bread, chopped or whizzed to make breadcrumbs
Handful grated parmesan

Saute the leek in the butter over a medium-high heat; add the broccoli florets and stir briefly to soften. Add the cheese sauce and stir on a low heat until it's hot. Meanwhile, cook and drain the penne. Turn penne and vegetables into an oven dish, and stir to combine. Sprinkle with the breadcrumbs and finely-grated parmesan, and put under a hot grill until toasty and bubbling on top. Serve with garlic bread.