In large bowl, beat 1 cup granulated sugar and 1/2 cup butter with electric mixer on medium speed, or mix with spoon. Beat in 1 cup eggnog, the sour cream, rum extract and eggs until blended. Stir in 2 1/2 cups flour, the baking powder, baking soda and salt. Spread in pan. Sprinkle Streusel Topping over batter. Cover and refrigerate at least 8 hours.