Preheat the oven to 180 degrees Celsius. Lightly brush the potatoes with olive oil and space evenly on a lined baking tray. Once the oven is ready, bake the potatoes for 40 minutes to an hour (depending on their size) or until you can insert a knife through the potato. Remove from the oven and allow to cool.
While the potatoes are cooking, weigh out your flours into a large mixing bowl. Add the salt, and mix to thoroughly combine.
Once cooled, use your hands to peel off the potato skins. These leftover skins can be sprayed with oil and baked, to make delicious potato skin chips.
Once the potatoes are peeled, place them in a high-speed blender, and blend until a super sticky, gelatinous paste forms. It should be mostly free of lumps, but don’t push your blender too hard because it is a very sticky mixture. I use a Nutribullet for this, and I ensure I give it a few breaks in between blending, particularly because there is nowhere for the hot air to escape.
Once you have a smooth, sticky paste, decant it into the flour bowl. Use a spoon at this stage to mix everything together. It will take a little while, but eventually you should have a shaggy, somewhat sticky ball of gnocchi.
Once it is mostly mixed, use your hands to get in there and finish the job. Add extra rice flour or tapioca flour to this mixture as you see fit. The mixture should be sticky but manageable. Note that the more flour you add, the chewier the gnocchi will become, so try to keep it to bare necessities.
Liberally flour a dry, clean bench space with tapioca flour, and divide the dough into four or so balls. Use floured hands to roll each ball out into a long, thin, gnocchi sized rope. Use a sharp floured knife to cut the rope into individual pieces. Place the pieces on the lined tray with space between each piece. Repeat with all the balls of gnocchi until you have used it all up.
Heat a medium to large saucepan of salted water over a high heat. Once boiling, carefully lower the gnocchi into the water, in batches of 10-12 pieces at a time (saucepan size dependent.) Once the gnocchi have risen to the surface, allow to cook for 2-3 minutes before removing from the water. Test one piece of gnocchi to check that they’re cooked and adjust the cooking time for the rest of the gnocchi if necessary.
Drain each piece of cooked gnocchi well before transferring to large mixing bowl. Drizzle them lightly with olive oil as they go into the bowl – because they’re filled with a mixture of starches, they will stick to each other if they’re not oiled.
Repeat until all the gnocchi is cooked.