Arrange 1 won ton wrapper on a clean, flat surface. (Cover remaining wrappers with plastic wrap or a damp towel to prevent drying out.) Lightly moisten wrapper with water. Place about 1 Tbsp. mashed sweet potatoes in center of wrapper; fold 2 opposite corners together over mashed sweet potatoes, forming a triangle. Press edges together to seal, removing any air pockets. Cover with plastic wrap or a damp cloth. Repeat procedure with remaining wrappers and mashed sweet potatoes.
Cook pockets, in 2 batches, in boiling water to cover in a large Dutch oven over medium-high heat 3 minutes. Remove with a slotted spoon, and drain well.
Sauté pockets, in batches, in hot oil in a large nonstick skillet over medium-high heat 2 to 3 minutes on each side or until golden brown. Drain well. Arrange pockets on a serving platter.
Melt butter in skillet over medium heat; stir in sage. Cook, stirring occasionally, 4 minutes or until butter is lightly browned. Pour over pockets, and add salt to taste.
*1 (15-oz.) can cut sweet potatoes in syrup, mashed, may be substituted.