How to Make It
Combine 1/2 cup water and flour in a 6-quart electric slow cooker, stirring with a whisk. Stir in stock and next 8 ingredients (through mushrooms). Add chicken thighs to stock mixture; submerge in liquid. Cover and cook on LOW 7 1/2 hours. Remove chicken. When cool enough to handle, remove bones from chicken; discard bones.
Add oil and pasta to slow cooker; cover and cook on HIGH 15 minutes or until pasta is done. Stir in spinach until wilted. Divide pasta mixture among 8 shallow bowls; top evenly with chicken. Sprinkle with Parmesan cheese.