For dough: combine 2 cups flour, sugar, salt and yeast in large bowl; add milk, butter and egg; beat 1 minute; stir in enough remaining flour to make a soft dough; knead dough on floured board for 5 minutes; place in greased bowl; cover with plastic wrap; let rise in warm place until doubled, about 1 1/4 hours.
For topping: bring brown sugar and butter to a boil, stirring constantly; remove from heat; stir in syrup; pour into 13" x 9" pan; sprinkle pecan halves on top.
For filling: punch down dough; roll out into 15" x 10" rectangle; spread with butter.
Combine pecans, brown sugar and cinnamon; sprinkle over dough; starting at long side, roll up tightly, pinching seam to seal; cut into 15 pieces; place in pan; cover tightly with plastic wrap; refrigerate 12-48 hours.
Preheat oven to 350°F.
Bake uncovered for 25-30 minutes, or until golden; let stand 3 minutes in pan, then invert onto serving platter.