Rosemary Mashed Sweet Potatoes with Shallots

From November Cooking Light I was looking for a lower calorie alternative to the Pecan streusel crusted high caloric sweet potatoes casserole I normally make  --this did not disappoint --the caramelized shallots and rosemary were a great touch, Again can be made ahead which is great.

• 5 1/2 teaspoons extra-virgin olive oil, divided
• 1/2 cup thinly sliced shallots (about 2 medium)
• 1 1/2 teaspoons brown sugar
• 1 1/3 pounds sweet potatoes, peeled and diced
• 2 teaspoons finely chopped fresh rosemary
• 1/4 teaspoon coarse sea salt
• 1/4 teaspoon black pepper
• 1. Heat 4 teaspoons oil in a medium skillet over low heat. Add shallots to pan, and cook for 5 minutes, stirring occasionally. Sprinkle with sugar; cook 20 minutes or until shallots are golden, stirring occasionally.
  2. Place potatoes in a medium saucepan; cover with water. Bring to a boil; cook 8 minutes or until tender. Drain. Place potatoes in a large bowl; beat with a mixer at medium speed until smooth. Add rosemary, salt, and pepper; beat until blended. Spoon into a bowl; top with shallots, and drizzle with remaining 1 1/2 teaspoons oil