2 lbs. red bliss potatoes [or new potatoes], peeled if desired and cut into 2-inch chunks
1 cup Hellmann's® or Best Foods® Real Mayonnaise
1/2 cup grated Parmesan cheese
1/2 cup chopped red onion (optional)
Cover potatoes with water in 4-quart saucepot. Bring to a boil over high heat. Reduce heat to low and simmer 15 minutes or until potatoes are tender; drain. Return potatoes to saucepot; mash. Add remaining ingredients. Season, if desired, with salt and ground black pepper.