Fire up your oven, aiming for 852°F to 950°F (450°C to 500°C) on the stone.

Tip: Use an infrared thermometer to for a fast, accurate reading

Melt half of the butter in a medium-sized saucepan on medium heat, then add the chicory heads and brown on all sides. Once browned, pour water into the pan until the chicory is half covered, then cover with a lid and bring to boil; cook until the chicory is tender. 

Tip: This should take about 5 to 8 minutes, and the best way to check is by pricking the chicory with a fork until it easily pierces through.  

Once tender, carefully drain the cooked chicory with a colander, saving the liquid in a separate container for use later. Let the chicory cool, then squeeze out as much water as you can, then set aside.

In a saucepan, melt the remaining butter over medium heat, then add the flour and mix with a whisk to make a roux. Cook the roux for a few minutes, then slowly add the milk, whisking constantly. Add the chicory cooking water while continuing to whisk, aiming for a consistency like thick paint. 

Next, squeeze the lemon juice, a pinch of salt and pepper, then the nutmeg into the roux. Then add ¼ cup (50 grams) of Emmental cheese, and mix briefly before removing from the heat. 

Once the roux has cooled, slice the chicory into thin rings and set aside.

Lightly flour a work surface and set your dough ball on it. Use your fingers to push the air from the center out to the edges. Stretch the dough out to a 12-inch (30- centimeter) round base, then lay it over your lightly floured pizza peel. 

Use a large spoon or ladle to spread an even layer of the cheese sauce across the base. Add the ham pieces, then sprinkle an even layer of chicory over the top. Finally, top it off with the remaining cheese.

Slide the pizza off the peel and into the oven. Cook for 60 to 90 seconds, turning the pizza every 20 seconds to ensure an even bake.

Remove the pizza from the oven, cut into 8 slices and add another squeeze of lemon if you like, and enjoy!