Super Rich Carbonara

Directions

1. 1
   cook pasta according to package directions.
2. 2
   saute onions in 1/4 cup of butter until onions are transparent.
3. 3
   add mushrooms and beef cubes.
4. 4
   saute until beef cubes are dissolved.
5. 5
   add water, cheese, milk, and remaining butter.
6. 6
   bring to a boil while stirring occassionally.
7. 7
   simmer until the cheese dissolves.
8. 8
   add cornstarch mixture to desired consistency.
9. 9
   (I like it really thick so I use around 3 tbsp cornstarch disolved in very little water).
10. 10
    simmer for a few more minutes.
11. 11
    pour sauce over pasta and top with bacon, if desired.