We like this with Plenty of brown rice to catch the extra sauce. Adding the chicken frozen slows down the cooking somewhat, but this is still a relatively quick dish. Found in Not Your Mother's Slow Cooker Cookbook.
For the spaghetti crust, use 2 forks, a rubber spaula, or a wooden spoon to firmly press the spaghetti mixture evenly onto the bottom and up the sides of the pie plate. Build the edges high enough to hold all the filling.