Lightly spoon flour into dry measuring cups; level with a knife. Set aside 1 tablespoon sugar. Combine flour, remaining sugar, baking powder, salt, and baking soda in a large bowl; make a well in center of mixture.
Combine rind, juice, oil, and egg in a small bowl, stirring well with a whisk. Add to flour mixture, stirring just until moist. Fold in cranberries and walnuts. Spoon batter into 16 muffin cups coated with cooking spray. Sprinkle evenly with reserved sugar. Bake at 400° for 15 minutes or until the muffins spring back when touched lightly in center. Run a knife or spatula around outer edge of each muffin cup. Carefully remove each muffin; place on a wire rack.