Mix 2 cups of the flour, the yeast, sugar and salt in large bowl. Heat water and butter in 1-quart saucepan over medium heat, stirring occasionally, until very warm (120°F to 130°F). Add water mixture to flour mixture. Beat with electric mixter on low speed 1 minute, scraping bowl frequently. Beat on medium speed 1 minute, scraping bowl frequently. Beat in 2 eggs until smooth. Stir in enough remaining flour to make dough easy to handle.