Cream butter in a large mixing bowl; gradually add 1/4 cup sugar, beating until light and fluffy. Add egg yolks, one at a time, beating well after each addition. Stir in flour.
Press mixture into a lightly greased 15- x 10- x 1-inch jellyroll pan. Bake at 350° for 25 minutes or until lightly browned. Remove from oven; cool in pan. Spread preserves over baked crust.
Beat egg whites (at room temperature) in a medium mixing bowl until foamy. Gradually add remaining sugar, 1 tablespoon at a time, beating until stiff peaks form. Fold in vanilla. Spread meringue over preserves. Sprinkle with pecans.
Bake at 350° for 15 minutes or until lightly browned. Cool slightly; cut into 2- x 1-inch bars with a warm knife.