Put a large frying pan on a high heat, and once hot, add a good couple lugs of olive oil.
Cut your bacon into thick 1/2-inch/1 cm lardons, and add to the pan. Fry, stirring occasionally, for around 3 minutes, or until you've got a good bit of colour on the bacon and a lot of the fat has rendered out. Turn the heat down a little and add your bread to the pan, making sure you spread the croutons out so they take on some colour. Fry for another 3 minutes, or until they've sucked up all the wonderful flavour and are lovely, crisp, and golden.
For the dressing:
Put the extra-virgin olive oil, red wine vinegar, Dijon mustard, and a good pinch of salt and pepper into a clean jam jar. Put the lid on and give it a shake, then have a taste and make sure you've got the balance right. Cook's Note: You want it to be slightly too acidic at this stage, as you'll get quite a bit of saltiness from the bacon and French dressings tend to be quite sharp.
For the salad:
Once your dressing is made, get everyone around the table so they're ready to tuck in as soon as the salad is ready. Put your lamb's lettuce (mache) on a big platter, tear in the radicchio, then pour over that wonderful, thick dressing. Scatter over most of your walnuts and chives and all the croutons and lardons. Quickly mix it all up with your clean hands so that every single leaf is coated.
Use the tip of a knife to crumble off little nuggets of Roquefort and let them fall straight on to your salad. Finish by scattering over the rest of the walnuts and chives from a height, and tuck in!