1. Preheat oven to 350°. Whisk together flour, 1 cup sugar, baking powder, nutmeg, and salt in a large bowl. Make a well in center of dry ingredients.
2. Combine eggs, milk, and 1/3 cup melted butter in a small bowl. Pour mixture into well of dry ingredients, stirring just until moistened. (Batter may be lumpy.) Spoon into lightly greased muffin cups, filling three-fourths full.
3. Bake at 350° for 20 to 25 minutes or until wooden pick inserted in center comes out clean.
4. Combine remaining 1/4 cup sugar and cinnamon in a small, shallow bowl. Let muffins cool just enough to handle; dip tops of hot muffins into remaining 1/4 cup melted butter, then into sugar mixture until coated. Serve warm.