In a large mixing bowl combine 3 cups of the flour and the yeast.

In a saucepan heat the 1-1/2 cups milk, the 1/2 cup margarine, the 1/2 cup sugar, and salt just until warm (120 degrees F to 130 degrees F) and margarine is almost melted, stirring constantly. Add to flour mixture. Add eggs. Beat with an electric mixer on low speed for 30 seconds, scraping sides of bowl constantly. Beat on high speed for 3 minutes. Using a 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 moderately soft dough that is smooth and elastic (3 to 5 minutes total). Shape into a ball. Place in a greased bowl, turning once. Cover; let rise in a warm place until double (about 1 hour).

For filling, in a small bowl combine the 3/4 cup sugar, 1/2 cup margarine or butter, cinnamon or orange peel, and the 2 teaspoons flour; set aside.

Punch dough down; divide in half. Cover and let rest 10 minutes. On a lightly floured surface roll each half of the dough into a 12-inch square.

Spread half of the filling over each dough square. If desired, sprinkle with half of the nuts, chocolate, or raisins. Roll each square up into a spiral; pinch edges to seal. Slice each roll into 8 pieces. Place 8 pieces in a greased 13x9x2-inch baking pan. Repeat with remaining pieces using another 13x9x2-inch pan or a 12-inch pizza pan.

Cover loosely with clear plastic wrap, leaving room for rolls to rise. Refrigerate 2 to 24 hours. Uncover and let stand at room temperature for 30 minutes. (Or, dont chill dough. Instead, cover loosely; let rise in a warm place until nearly double, about 45 minutes). Break any surface bubbles with a greased toothpick.

Bake in a 375 degree F oven for 20 to 25 minutes. Remove from pans. Cool slightly on a wire rack.

Meanwhile, in a mixing bowl combine powdered sugar and vanilla. Add enough milk to make of drizzling consistency. Spread over rolls. Makes 16 servings.