Peel the potatoes, place them in salted water in a medium pot, turn on heat and bring to a boil. Cook potatoes until a knife slides through with ease, about 30 minutes. Strain potatoes and set aside.

While your potatoes cool, heat the butter and milk together in a separate pan until the butter is melted, then turn off the heat and set aside. Using a masher, combine your potatoes with the butter and milk mixture until creamy. Season with salt to taste. 

Meanwhile, turn on your home oven or fire up your Ooni oven, aiming for 220°C (425°F).  Peel and slice the onions, toss with grapeseed oil and salt, and roast until lightly browned, about 15 minutes.

Fire up your Ooni oven, aiming for 450°C to 500°C (850°F to 950°F) on the stone baking board inside. 

Place a dough ball on a lightly floured work surface. Push the air from the centre out to the edge using your fingers. Stretch the dough out to a 12-inch-round base, then keep your dough on the countertop or lay the stretched dough over your lightly floured pizza peel.

Top the dough with one ounce (30 grams) each of raclette, bacon, and onion and two ounces (60 grams) of mozzarella.

Using a spoon, dollop mashed potatoes onto the pizza, filling the spaces where there’s no cheese. 

Move your topped pizza onto a peel, if you haven’t already. Slide the pizza off the peel and into the oven. Cook for 60 to 90 seconds, turning the pizza regularly to ensure an even bake. 

Remove from the oven and sprinkle on the chives.

Slice and enjoy.