Preheat oven to 350 degrees.
Spray 9x13" casserole with non-stick spray.
Combine white sugar and cinnamon in a ziplock.
Cut one tube of biscuits into quarters. Place 5 or 6 pieces of biscuit into ziplock with sugar mix and toss to coat. Transfer coated biscuit pieces to prepared pan. Continue until all the pieces from the first pan are coated in sugar.
Slice apple into small bite sized pieces. Add to sugar bag and toss to coat. Add apple chunks to biscuits in pan.
Top with pecans (if using).
Cut the remaining can of biscuits into quarters. Toss in sugar to coat, and add to pan.
Prepare caramel sauce by melting 1 stick of butter in sauce pan. Add one cup brown sugar. Bring to a boil, and boil one minute, stirring constantly. Pour caramel sauce on top of biscuits, and spread around.
Bake @ 350 degrees for 25-30 minutes.