There are many recipes using mashed potatoes at this site..
http://www.kitchenlink.com/abm.html (many are new)
Type "potato" in the search box and many recipes will appear.
Here are a couple.
JoAnn
Mashed Potato Pizza Dough
1 1/2 teaspoons dry yeast 
1 1/2 cups bread or all purpose flour 
3/4 cup whole wheat flour 
1/2 cup mashed potato 
1 teaspoon dried oregano 
1 teaspoon dried thyme leaves 
1/2 teaspoon salt 
3/4 cup water 
Add all ingredients according to machine's manufactuer. Process on the
dough cycle. 
At the end of cycle, remove the dough from machine. Preheat oven to
400F. Divide dough in
half. Roll to 10 inch circles on floured board and place on baking pans
or sheets. Cover with
you choice of toppings. Bake 20 minutes or until browned to your taste.
Makes 2 (10 inch). 
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MMMMM----- Recipe via Meal-Master (tm) v8.04
      Title: ITALIAN CHEESE-POTATO BREAD
 Categories: Breadmaker
      Yield: 1 Servings
MMMMM-------------------LISA CRAWLEY  TSPN00B------------------------
  2 1/2 ts Dry yeast
      3 c  Flour
      1 ts Sugar
      1 ts (scant)Salt
    2/3 c  Potatoes; mashed
      1 c  Monteray Jack Cheese;cubed
      2    Eggs
    1/3 c  Milk; warmed
      2 ts Dried Oregano
  Place all ingredients in breadmachine according to manufacturer's
  instructions.  Bake on White Bread setting. Makes a dense loaf of very
  flavorful bread. Modified by Wendy Ceracche DBCP84B I used Gouda
  cheese since I didn't have any Monterrey Jack cheese.
MMMMM
MMMMM----- Recipe via Meal-Master (tm) v8.04
      Title: MADELEINE'S NEIGHBORLY BREAD
 Categories: Pam vkbb14a, Breads, Bmm, Breadmaker
      Yield: 1 Servings
           1 pound loaf
    3/8 c  Milk
    1/4 c  Potato water
  1 1/3 c  Whole wheat flour
    2/3 c  Bread flour
    1/4 c  Plain mashed potato*
      1 ts Salt
      1 tb Applesauce (butter)
      1 tb Honey
      2 ts Yeast
  Crust light.
MMMMM
                     *  Exported from  MasterCook  *
                    KAREN'S HERB OATMEAL-POTATO BREAD
Recipe By     : 
Serving Size  : 1    Preparation Time :0:00
Categories    : Breads
  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
     1/2   c            Mashed potato
   1                    Extra-large egg
   4       tb           Butter, at room temperature
                        OR use vegetable oil
     3/4   c            Water
     3/4   ts           Dried thyme, rosemary,
                        Oregano, or basil OR
                        A combination
   2 1/2   c            Unbleached white flour
     1/2   c            Quick-cooking oats
   1       t            Salt
   1       tb           Sugar
   1       tb           Active dry yeast
                        AFTER BEEP
   2       tb           Sunflower seeds
  Place all the ingredients except the sunflower seeds in machine in
order
  suggested by manufacturer and program for raisin bread. When beeper
sounds,
  add the sunflower seeds.
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