In this task, you will be presented with the directions of a recipe separated by "," and have to fill in the "___" which is a step that is missing from the recipe.

Cook pasta in a large saucepan of boiling salted water according to package directions. Add vegetables during last 2 mins of cooking. Drain well; return to pan.,Meanwhile, melt butter in a medium saucepan on medium heat. Add flour and cook, stirring, for 1 min. Remove from heat.,Gradually stir in milk until smooth. Return to heat and cook, stirring, for 3-4 mins until mixture boils and thickens.,Reduce heat to low and simmer for 3 mins. Add to pasta and vegetable mixture along with 1 cup of the cheese; mix well. Season to taste.,______,Broil 8-10 mins until cheese is melted and golden.
Preheat broiler to high. Pour mixture into a shallow 2-quart baking dish. Sprinkle with remaining 1 cup cheese.