In a large mixing bowl mix milk, butter, sugar, salt, and vanilla. Add yeast mixture and half of the flour. Cover and let rest 15 minutes. Add remaining flour and eggs, one at a time, beating well after each addition. Cover and let rise in a warm place until double, about an hour. The dough will be very soft.
In a shallow bowl, combine sugar, cinnamon, and pecans. Drop dough by large spoonfuls into the cinnamon mixture, rolling each piece until about 7 or 8 inches long. Twist into desired shapes and place on well-greased baking sheet. Bake for 12 to 15 minutes at 375°. Baked cinnamon twists may be frozen.