The boys were asking for pies - their timing was perfect. With a frost coming, it was time to bring in the last bounty of the garden. The rhubarb was a little green and the apples a bit pecked and bruised.
I used a standard large double-crust pie recipe from Betty Crocker and added a 1/4 cup sugar. When the dough just came together, I gently cut and rolled the dough into 12 balls and placed them into a standard muffin tray to chill in the fridge while the sauce continued to cook a bit more and then cool.
Preheat oven to 350F. After the dough has chilled and the sauce cooled. Roll each dough ball into a palm-sized circle and place back into the muffin pan. After cooking, the sauce became more caramel colored then green. Fill each pie with rhubarb-apple sauce. There was plenty of sauce left over for another day.