In large bowl, beat butter with electric mixer on medium speed about 1 minute or until creamy. Add half of the 1 cup granulated sugar in 2 stages, beating on medium speed about 2 minutes after each addition until butter and sugar are pale and fluffy. Add 2 eggs and 1 egg yolk, one at a time, beating well and scraping side of bowl after each addition. Beat in vanilla just until combined. Using rubber spatula, fold flour mixture into butter mixture until combined.