Combine first 3 ingredients in a 1-cup glass measuring cup; let stand 5 minutes.
Beat 1/2 cup softened butter at medium speed with a heavy-duty electric stand mixer until creamy. Gradually add 1/2 cup granulated sugar and 1 tsp. salt, beating at medium speed until light and fluffy. Add eggs and next 2 ingredients, beating until blended. Stir in yeast mixture.
Combine 4 1/2 cups bread flour and 1/4 tsp. nutmeg. Gradually add flour mixture to butter mixture, beating at low speed 1 to 2 minutes or until well blended.
Sprinkle about 1/4 cup bread flour onto a flat surface; turn dough out, and knead until smooth and elastic (about 5 minutes), adding up to 1/4 cup bread flour as needed to prevent dough from sticking to hands and surface. Place dough in a lightly greased large bowl, turning to grease top. Cover and let rise in a warm place (85°), free from drafts, 1 1/2 to 2 hours or until doubled in bulk.
Meanwhile, preheat oven to 350°. Bake pecans in a single layer in a shallow pan 8 to 10 minutes or until toasted and fragrant, stirring halfway through.
Punch dough down; turn out onto a lightly floured surface. Roll into a 16- x 12-inch rectangle. Spread with 1/2 cup very soft butter, leaving a 1-inch border around edges. Stir together brown sugar, cinnamon, and remaining 1/2 cup granulated sugar, and sprinkle sugar mixture over butter. Chop chocolate; sprinkle over sugar mixture.
Top with pecans. Roll up dough, jelly-roll fashion, starting at 1 long side; cut into 16 slices (about 1 inch thick).
Place rolls, cut sides down, in 2 lightly greased 10-inch round pans. Cover and let rise in a warm place (85º), free from drafts, 1 hour or until doubled in bulk.
Bake at 350° for 20 to 22 minutes or until rolls are golden brown. Cool in pans 5 minutes. Brush rolls with Cream Cheese Icing. Serve immediately.