In a medium pot, boil water and cook noodles as directed on the packaging. Reserve 1 cup of the pasta water for later.
In a blender, add milk, cottage cheese, half the cheddar cheese, ground mustard, garlic powder, and pepper, and blend until smooth.
In a large pot, add cheese mixture and heat on medium until hot but not boiling, stirring occasionally.
Add frozen peas, stir, and continue to cook on low for 4-5 minutes or until peas are cooked through.
Turn off the heat and stir in the rest of the cheddar cheese until melted.
Stir in pasta and add ½ cup pasta water. Let mixture set for 5 minutes before serving. If desired, add any additional pasta water until sauce reaches desired consistency. Serve and enjoy!