In a sauce pan, melt butter. Add walnuts and Ramen noodles. Cook 5 minutes or until slightly brown.
Cool on paper towel.
In a large bowl add broccoli, romaine, onions, noodles, and walnuts.
To make the dressing, combine vegetable oil, sugar, vinegar, and soy sauce in a sauce pan. Bring to a boil and cook for 1 minute. Remove from stove and let cool.
Pour dressing over salad just before serving.