Step 1:
1. Cook pasta to packet instructions, drain and then put in the bottom of a oven proof dish Step 2:
2. Tear/ grate the bread until they are crumbs Step 3:
3. Melt some butter in the pan and then place the breadcrumbs in with it. Coat thoroughly and remove from heat. Step 4:
4. Melt some more butter in a pan and then add flour until it forms a dough, cook for about 2 minutes (it is best to do this at a low heat) Step 5:
5. Add milk in steady and slow stages until the sauce is at the texture you want (you can add mustard at this point if you wish). Step 6:
6. Stir in the cheese until it has melted and remove pan from the heat. Step 7:
7. Pour sauce over the pasta and then scatter the breadcrumbs on top Step 8:
8. Bake in the oven until the breadcrumbs are crispy (20- 30 minutes is normally about right) 