Boil water in a large pot on the stove.
Prepare pasta according to package instructions, reserving 2/3 cup of the pasta water.
In a medium skillet, add the olive oil and butter.
Once melted, add the black pepper, and stir for about one minute.
Next add half of the reserved water and let simmer for about two minutes.
Add the cooked pasta and coat well.
Finally, add the egg yolk and parmesan cheese, using tongs to make sure all of the spaghetti is evenly coated
Plate and add more cheese and pepper to taste.
You can add salt, but I find that it's salty enough from the parmesan.ENJOY!!!!