Pre-heat your oven to 220C / 200C fan / gas mark 7 / 425F.

Cook the pasta according to the pack instructions / your own preferences in a large saucepan. (See Note 2.) For best results, slightly undercook the pasta. This is because the pasta will cook a little more when baked in the oven.

Add the broccoli and cauliflower to the pasta pan for the last 4 minutes of cooking time. (See Note 2.) When the broccoli, cauliflower and pasta have finished cooking, drain and tip into a large, shallow oven dish.

Meanwhile, place the lardons in a small frying pan over a high heat and fry until crisp and golden (about 3 minutes). Turn off the heat and tip into the oven dish.

Next, make the cheese sauce. Melt the butter in a medium sized pan over a low heat. When the butter is foaming, add the flour and stir until it’s mixed in. Then keep cooking for 2 minutes, stirring frequently. It takes guts to do this. It looks like something is going to go wrong but it won’t!

Very gradually add the milk, stirring constantly. Make sure each bit of milk is incorporated before adding the next bit. If you do this slowly on a very low heat, you should end up with a perfectly smooth cheese sauce with no lumps and no need to whisk. However, if it does go wrong for some reason, you can always use a whisk to beat out the lumps.

When all the milk is incorporated, add the mustard, salt (if using – see Note 1.) and pepper. Then add half the cheese, stir to combine and turn off the heat.

Pour the cheese sauce over the pasta, vegetables and lardons (which should by now be in the oven dish), stir to mix everything together and sprinkle over the remaining cheese.

Bake in your preheated oven for 15 minutes, or until brown and bubbling.

Serve on its own or with a green salad and/or garlic bread.