Preheat your oven to 375ºF. Start by pricking the potatoes all over with a fork. This will allow steam to escape while they bake. Pour a small mound of Kosher salt in the center of a rimmed baking sheet to create a bed for the potatoes. Nestle them on top of the salt. Bake until they are tender, which should take about 45 minutes to 1 hour. You want them completely soft!
Once the potatoes are baked and still warm, it’s time to peel them. The skins should come off easily, but feel free to use a paring knife for any stubborn bits. After peeling, chop the warm potatoes into large chunks and press them through a ricer on to a lightly floured work surface. This will give you that fluffy texture needed for good gnocchi. Let the riced potatoes cool for about 3 to 4 minutes.
While the potatoes are cooling, bring a large pot of water to a boil and add two generous pinches of Kosher salt. Make a well in the center of the riced potatoes on your work surface. Sprinkle ½ cup of flour around the well, then crack the egg into the center. Using a fork, beat the egg in a circular motion, gradually pulling in some of the flour and potato from the sides. Continue until the egg is fully incorporated.
Now it’s time to knead! Gently knead the dough with your hands just until it comes together. If it’s too sticky, you can add more flour in small amounts until it becomes smooth. Be careful not to overwork the dough; this can make the gnocchi tough. Pinch off a small bit of dough and toss it into the boiling water to test if it holds its shape. If it falls apart, knead in a bit more flour and test again.
Divide the dough into four pieces. Roll each piece into a rope about ½ inch thick. Cut each rope into ½-inch lengths to form individual gnocchi pieces. Place them on a parchment-lined baking sheet and set aside while you prepare the sauce.
In a large skillet, melt the butter over medium heat. Cook it until it turns a light brown color and develops a nutty aroma. This is the secret to a delicious brown butter sauce! Add the sage leaves to the skillet and let them sizzle for about 1 minute, then take the sauce off the heat.
Now, drop the gnocchi into the boiling water. They’re ready when they float to the surface, usually within 30 seconds to 1 minute. Once they’re floating, use a slotted spoon to scoop them directly into the brown butter sauce.
Return the skillet to medium-low heat. Toss the gnocchi in the brown butter sauce. Add a pinch of red pepper flakes to taste and two tablespoons of the gnocchi cooking water to help combine everything. Remove from heat and top with Parmesan cheese. For a lovely presentation, shave some cheese with a vegetable peeler.
To serve, spoon the gnocchi into shallow bowls, topping with additional Parmesan cheese as desired. Enjoy this delightful dish warm and fresh!
