Dissolve yeast in water. Add sugar, salt, and about half the flour. Beat thoroughly for 2 minutes. Add egg and butter. Gradually beat in remaining flour until smooth. Cover bowl with damp cloth and place in refrigerator.
Divide the dough into four parts. For each part: knead thoroughly; roll out onto floured surface into approximately 12" X 6" rectangle; spread with some of softened butter and sprinkle with cinnamon sugar; with long edge roll dough into a log; seal the last edge; cut into 12 pinwheels.
In each round cake pan, pour ¼ cup butter and 1/3 cup brown sugar (mixed together). Place pecan halves on bottom of pan. Place 12 pinwheel rolls in pan. Let rolls rise 1½-2 hours at room temperature. Bake for 12-15 minutes in a 400° oven. While still warm, place dinner plate face down on pan of rolls and invert. Serve warm!
Makes 4 dozen rolls. Pans of baked rolls may be frozen.