Melt 3 Tbsp. butter in medium saucepan on medium heat. Whisk in flour; cook 2 min., stirring constantly. Gradually stir in milk. Bring to boil; cook and stir 3 to 5 min. or until thickened. Add VELVEETA; cook 3 min. or until melted, stirring frequently. Stir in macaroni.
Spoon into 2-qt. casserole sprayed with cooking spray. Melt remaining butter; toss with cracker crumbs. Sprinkle over casserole.
Bake 20 min. or until heated through and crackers are golden brown.
Recipe by Bear In The Pantry at https://bearinthepantry.com/wp/easy-homemade-macaroni-and-cheese/