In a small saucepan heat milk just until warm (105 degrees F to 115 degrees F). In a large bowl combine warm milk and yeast; stir to dissolve yeast. Let stand 5 to 10 minutes or until foamy.
Add 1/2 cup of the pumpkin and next four ingredients (through salt) to yeast mixture. Beat with a mixer on medium until combined. Add half of the flour; beat on low 30 seconds, scraping bowl as needed. Beat on medium 3 minutes. Stir in remaining flour. Shape into a ball (dough will not be smooth). Place dough in a greased bowl, turning once to grease surface. Cover and let rise in a warm place until nearly double in size (45 to 60 minutes).
Butter a 9x5-inch loaf pan. Turn dough out onto a lightly floured surface. Roll into a 20x12-inch rectangle. In a small bowl combine remaining 1/2 cup pumpkin and 3 Tbsp. melted butter; spread over dough. Combine brown sugar and cinnamon; sprinkle over pumpkin mixture. Cut dough crosswise into five 12x4-inch strips. Stack strips, then cut crosswise into six 4x2-inch pieces, leaving stacks intact. Loosely stagger pieces, cut sides up, in prepared pan. Cover and let rise in a warm place until nearly double in size (about 45 minutes).
Preheat oven to 350 degrees F. Bake 35 minutes or until golden, covering loosely with foil the last 10 minutes if needed to prevent overbrowning. Cool in pan on a wire rack 10 minutes. Remove from pan. Drizzle with Cinnamon Glaze and, if desired, sprinkle with pecans. Cool 20 minutes more.
Stir together powdered sugar, cinnamon, vanilla, and enough milk to make glaze drizzling consistency.