Mashed Potatoes With Cantal
Place the potatoes and 1 teaspoon of salt in a heavy medium pot, cover with water by 1 inch, and bring to a boil. Reduce the heat to a simmer and cook until the potatoes are fork-tender, 20 to 25 minutes. Drain in a colander.
Return the potatoes to the pot, set over low heat, and add the butter. Using a potato masher, mash the butter into the potatoes. Add the milk, the remaining 3/4 teaspoon salt, and the pepper and mash with the potato masher over medium-low heat to incorporate the ingredients and achieve a light texture, 4 to 5 minutes. Add two-thirds of the Cantal and stir until melted and smooth.
Serve immediately, with the remaining cheese crumbled on top.