Mix cookie crumbs, flour, carrots, walnuts, brown sugar and baking powder in medium bowl; set aside. Blend egg, milk and margarine or butter in small bowl; stir into flour mixture just until moistened. Spoon into 12 greased 2 1/2-inch muffin-pan cups. Bake at 400 F for 20 to 25 minutes or until done. Cool slightly; serve topped with cream cheese, if desired.
Prepare batter as above. Fill 6 double paper-lined microwavable muffin-pan cups 2/3 full. Microwave at HIGH (100% power) for 2 1/2 to 3 1/2 minutes or until toothpick inserted in centers comes out clean, rotating dish 1/2 turn after 1 minute. Let stand 1 minute on heat-proof surface; remove to rack. Repeat with remaining batter.