Beef and french fries

8 tb Oil
      2 lg Potatoes, matchstick cut
           Can use frozen
      1 md Onion, thinly sliced
      2    garlic cloves, minced
     10 oz Sirloin steak, thin slice
      2 ts Cornstarch
      3 ts Water
      1 ts Sugar
      2 ts Fish sauce, Nuoc Mam
           Pepper, lots
 
  1.  Pour 6 tablespoons of the oil into a flat skillet, add the potatoes and
  fry until brown.  Drain the oil and set potatoes aside to drain on paper
  towels. 2. Fry the onion and garlic in oil, then add the beef and fry for
  about 1 minute or until meat is browned but not tough. 3. Mix the
  cornstarch, water, sugar and fish sauce in a small bowl, blending well. Add
  this to the beef and stir..add more water if needed to make a light not too
  thick sauce. 4. Fold in potatoes or...remove the potatoes to a serving dish
  then spoon beef and sauce over the potatoes. 5. If you like, sprinkle with
  lots of black pepper.