Cook macaroni in boiling salted water 4 minutes. Drain and rinse. Set aside.
In large saucepan or dutch oven, melt butter over low heat, being careful not to burn. Add flour. Cook for 1-2 minutes. Do not brown.
Add milk slowly, stirring constantly. Stir in cheeses; cook over low heat until cheese is mostly melted .
Add salt, pepper, paprika and bread crumbs. Add macaroni. Mix together gently.
Pour into extra large buttered (or cooking spray) baking or casserole dish.
Bake uncovered at 350 degrees for 25 minutes. Remove from oven then add 1/2 cup shredded cheese on top. Sprinkle with additional paprika. Bake at 400 degrees until lightly browned on top. About 15 minutes. May brown under broiler for a couple of minutes. Watch carefully to prevent burning.
NOTE: Use a large deep size deep casserole dish or divide into two casserole dishes as this recipe makes a lot.