Bring a tall pot of water to a boil. Add some oil and salt. Add your pasta. Cook according to your pasta manufacturer's instructions. However, test it to make sure it's ready a minute or two before. You want to be sure that the pasta still has a little firmness (al dente) and is not mushy.
Drain the pasta using a colander. Set aside.
In the same pot, add the butter. Lower the heat to a low-medium temperature. Occasionally stir the butter around the pot with a wooden spoon. The butter will go through stages until it gets to a nutty sweetness. First, the butter will melt. Then, the butter will foam. Last, the butter will brown. Keep close watch so that it doesn't burn. Remove the butter from the heat and stir.
Gently toss the pasta into the browned butter sauce. Make sure you get that delicious browned butter sauce incorporated into all the pasta.
Then, toss about 5 to 6 ounces of the mizithra cheese with the spaghetti and browned butter.
Once you plate a portion of the spaghetti, top it with some additional mizithra cheese. Top with a little bit of parsley for color (optional).