Toss potatoes on a baking sheet with enough olive oil to coat generously and 1/2 teaspoon salt. Roast until tender and golden (but not brown, because they will bake again with the pizza), 20-25 minutes.
Toss the kale leaves in a bowl with 2 teaspoons olive oil and a large pinch of salt.
Adjust oven temperature to 475 (245) degrees.
Sprinkle half the Parmesan over the surface of your prepared dough. Scatter the kale evenly over the dough, followed by the potatoes and onion. Sprinkle the top with remaining Parmesan.
Bake until edges of the pizza are rich golden brown, about 15 minutes. Remove from the oven and immediately dollop the ricotta cheese over the pizza. Cool 5 minutes before slicing (it's easiest to slide the pizza out of the pan onto a cutting board to slice).
To make the dough:
Combine all the ingredients except for the salt in a heavy duty mixer fitted with the dough hook. Mix on medium speed until all the flour is incorporated.
Let the mixture rest for 30 minutes, then add the salt and knead on medium speed for 2 minutes. The dough should be smooth and elastic.
Cover the bowl with plastic wrap and set it on a counter for 1 hour, then place in the refrigerator for 24 hours.
About 2-3 hours before making pizza, transfer the dough to a floured surface and gently shape into a smooth ball. Place the dough on an 18 x 13-inch rimmed baking sheet coated with 1 tablespoon olive oil. Cover the dough with a towel and let it sit until doubled in size.
Stretch the dough to fit the pan, extending all the way to the edges of the pan. Add toppings and bake according to above recipe.
Notes
This recipe makes one 18-inch pizza. Plan on making the slow-rise dough one day ahead of serving or use a store-bought dough.