Bring a large salted pot of water to a boil. Add noodles and stir. 

Cook the noodles until they are al dente. Before straining noodles from the pot, remove about ¼ cup of the pasta water from the pot and set aside. 

Strain water from the noodles. 

Place the pot back on the stove top and turn heat to medium/low. 

Add butter to the pan. When the butter is melted, add the Greek yogurt and 2 tablespoons of pasta water, hot sauce, and pepper to the pot and stir until combined. 

Add the cheese powder packet to the Greek yogurt mixture and stir until there are no cheese powder clumps. If the clumps do not dissolve add 1 more tablespoon of pasta water to the pot. 

 Finally, add the cooked noodles to the pot and stir until all the noodles are covered by the cheese sauce. If the cheese sauce is too thick add a teaspoon of pasta water to the pot at a time until it reaches the desired consistency.