Image credit to: Boston Organics
1. Boil the potato in salted water and while it's still warm, carefully peel the skin. Using a fork, mash the potato in a bowl. Do not over mash but make sure there are no lumps.
2. Using a blender or food processor, grind arugula with egg yolk. Pour the mixture over the potato and roughly mix. Add a pinch of salt and shake some flour on top. Using a spatula, start working the dough. Keep adding flour as you go until the dough is moist but not sticky. Roll the dough into a log and using a knife, cut into bite-sized pieces (about 3/4 inches). To form the gnocchi: place one piece at a time and press it with your finger lightly so it forms the ridges. Then, roll it to form a curl. (See the instructional video.) Repeat with the rest of the dough.
3. Bring a large pot of water to boil. Boil the gnocchi (in batches, if your pot isn't large enough). It will take about 3 to 4 minutes for the pasta to become fluffy and float on top. Once your batch of gnocchi is done boiling, drain and drop it into a buttered pan over medium heat to sauté it for just a couple of minutes.
4. For the sauce: Melt 3 tablespoons of butter into a pan over medium-high. Once the butter is melted, stir in the lemon zest and chili flakes, if desired. Keep an eye as it can turn from brown to burned quickly! In couple of minutes, the butter will turn brown in color. Finally, drop the sautéed gnocchi into the pan with brown butter and mix until the gnocchi is coated in sauce.
5. Serve by drizzling on some fresh lemon juice, a few shaves of parmesan cheese. Serves 2-4.