To make the gnocchi: In a small bowl, mix the baking powder with the flour, then sprinkle it over the potatoes.
Add the cheese, yolks, salt, and nutmeg, mixing just until everything comes together into a cohesive ball.
Place the dough on a floured work surface, cover with the inverted bowl, and let it rest for 30 minutes.
Take about a third of the dough (145g) and roll it into a rope about 1/2" thick.
Use a bench knife to cut the rope 3/4"-long pieces. Using a gnocchi board or the back of a fork, roll the individual gnocchi to create ridges on one side and a little space in the middle.
Place the gnocchi on a parchment-lined baking sheet dusted with flour, cover lightly, and chill until ready to cook. Gnocchi may be stored in the refrigerator for up to a day, and in the freezer for several months.
To cook: Bring a large pot of heavily salted water to a boil. Reduce the heat to maintain a slow boil, and add the gnocchi.
Once gnocchi float to the surface, cook for 4 to 6 minutes. Drain cooked gnocchi and toss with your sauce of choice and/or fresh herbs; see “tips,” below for details on how to make a gorgonzola cream sauce.