Cheesy Seafood Pasta
["6 Tbsp. butter", "1/2 c. chopped onion", "1/3 c. flour", "1 1/2 tsp. salt", "3 c. milk", "2 c. macaroni shells", "1/2 lb. crabmeat", "1 1/2 c. shredded Cheddar cheese"]
["Saute onion in butter until soft.", "Add flour, salt and milk; microwave on High, stirring every 2 minutes until thickened.", "Add cheese."]
["butter", "onion", "flour", "salt", "milk", "macaroni shells", "crabmeat", "Cheddar cheese"]