Roasted Rosemary Potato Salad

by Katie of:
 pound bag red potatoes, quartered
1/4 c. olive oil
1 T. salt
1 t. pepper
2 T. fresh rosemary
1 c. mayonnaise
1 T. dijon mustard
1/2 t.. sugar
1 t. salt
1/2 t. cracked black pepper
1/2 onion, chopped
2 cloves garlic, minced
Preheat oven to 400º.  Line baking sheet with foil.  Place potatoes on sheet and drizzle with olive oil.  Mix potatoes around with your hands until well coated.  Sprinkle with salt and pepper and put in oven for 30-40 minutes or until skins are browning but inside is still fork tender.  Allow to cool.  Mix rosemary and next 7 ingredients to make sauce in bottom of large bowl.  After potatoes cool dump on top of sauce and mix to coat potatoes well.  Sprinkle with additional rosemary.