Polish Easter Bread (Babka Wielkanocna)

1/2 cup butter or margarine, softened
1/2 cup granulated sugar
3 egg yolks
1 package active dry yeast
1/4 cup warm water (105 to 115 degrees F)
2 teaspoons grated orange peel
1 teaspoon grated lemon peel
1 teaspoon ground cinnamon
1/2 teaspoon salt
4 cups all-purpose flour
1 cup lukewarm milk (scalded, then cooled)
1 cup golden raisins

Beat butter and sugar in large bowl until blended. Beat in egg yolks until well blended. Dissolve yeast in warm water. Stir yeast mixture, orange peel, lemon peel, cinnamon and salt into butter mixture. Stir in flour alternately with the milk, beating well after each addition, until soft dough forms. Stir in raisins. Cover; let rise in warm place until double, about 1 1/2 hours.

Stir down dough; spoon into greased and floured 10 x 4-inch tube pan or 12-cup Bundt cake pan. Cover; let rise until double, about 1 hour.

Heat oven to 350 degrees F. Bake until bread is golden brown, 35 to 40 minutes. Cool 5 minutes. Remove from pan; cool completely. Sprinkle with confectioners' sugar if desired.