Bake potatoes at 375° for 1 hour or until tender. Allow to cool. Place parsnips and garlic in a small saucepan; cover with water. Bring to a boil over medium heat. Reduce heat; cover and simmer for 20 minutes or until tender. Drain and mash.
Cut a thin slice off the top of each potato; discard. Scoop out the pulp, leaving a thin shell. In a bowl, mash potato pulp with parsnips and garlic. Beat in next five ingredients, using a hand mixer.
Stir in green onions. Spoon into the potato shells. Combine the Parmesan cheese and paprika; sprinkle over top. Place on a baking sheet. Bake, uncovered, at 375° for 20-30 minutes or until heated through.