Homemade macaroni and cheese is worth the effort for the comforting "welcome home" feeling it evokes. This version with a crushed crouton topping is the perfect blend of creamy and crunchy.
Cook macaroni according to package directions; drain thoroughly and return to pan.
Stir in butter and egg; mix mustard and salt with water and add to macaroni.
Add cheese, reserving ½ cup to sprinkle on the top.
Pour into a greased 2 quart casserole dish. Pour milk over noodles and cheese – do not stir it in but distribute evenly. Sprinkle with cheese and croutons.
Bake for about 45 minutes or until set and the top is brown.