1. Preheat oven to 425°. Bake potatoes on a lightly greased baking sheet 1 hour or until tender. Remove from oven, and let cool 10 minutes. Reduce oven temperature to 350°.
2. Cut potatoes in half lengthwise; carefully scoop out pulp into a large bowl, leaving shells intact. Mash together pulp, mayonnaise, next 3 ingredients, and 1/2 cup cheese. Spoon potato mixture into shells; sprinkle with remaining 1 cup cheese. Return potatoes to baking sheet.
3. Bake potatoes at 350° for 20 minutes or until thoroughly heated and cheese is melted. Garnish, if desired.
Note: To make ahead, prepare recipe as directed through Step 2. Cover and chill up to 24 hours. Let potato halves come to room temperature (about 30 minutes), and bake as directed in Step 3.