In a large mixing bowl, combine 1 cup of the flour, 1 cup warm milk, 2 teaspoons sugar and yeast. Beat with an electric mixer on medium speed 2 minutes, or until smooth. (The mixture will be thick and sticky.) Cover with plastic wrap. Let stand at room temperature 30 minutes or until bubbly.

Add the 2 eggs, 1/2 cup sugar, cocoa powder, finely chopped pistachio nuts, orange peel (if you like) and salt to flour mixture; stir in another 1/2 cup of the flour. Beat with an electric mixer on medium speed about 2 minutes, or until smooth. Add butter, a few pieces at a time, and beat until well combined. Using a wood spoon, stir in as much of the remaining flour as you can.

Turn dough out onto a lightly floured surface. Knead in enough of the remaining flour to make a moderately stiff dough that is smooth and elastic (6 to 8 minutes total). Shape dough into a ball. Place dough in a lightly greased bowl, turning once to coat all surfaces. Cover; let rise in a warm place until doubled in size (about 1 hour).

Punch down dough. Turn out onto lightly floured surface. Divide dough into three equal portions. Cover; let rest for 10 minutes.

Roll each portion of dough into an evenly thick rope that is 20 inches long. Line up the 3 ropes, 1 inch apart, on the lightly floured surface. Starting in the middle, braid by bringing left rope underneath center rope; lay it down. Then, bring right rope under new center rope; lay it down. Repeat to end. On the other end, braid by bringing outside ropes alternately over center rope to center. (Braid the ropes loosely so the bread has room to expand.) Join ends of braid to form a wreath. Carefully transfer wreath to a greased baking sheet, placing a greased ball of foil in center to help hold shape. Cover; let the dough rise until almost doubled in size (45 to 60 minutes).

Stir together 1 egg and 1 tablespoon milk. Brush over the top of the wreath. Bake in a 375 degree F oven about 25 minutes, or until bread sounds hollow when lightly tapped. If necessary, cover loosely with foil the last 10 minutes to prevent overbrowning. Remove from baking sheet; cool slightly. Remove ball of foil from center.

Spread the chocolate bread with Chocolate Icing. Sprinkle with additional pistachio nuts, if you like. Serve warm or cool. Makes 16 to 20 servings.

In a small saucepan, melt 1/2 cup milk chocolate pieces and 2 tablespoons butter over low heat, stirring frequently. Remove from heat. Stir in 1 cup powdered sugar and 2 tablespoons hot water. If needed, stir in additional hot water to make a smooth and creamy icing of spreading consistency. Makes 3/4 cup icing.