In deep fryer or 2-quart heavy saucepan, heat oil over medium heat to 350 degrees F.
Separate crescent dough into 4 rectangles. Firmly press perforations to seal. Stack 2 rectangles on top of one another. Fold in half widthwise to make tall stack. Repeat with remaining 2 rectangles.
To make 2 doughnuts, use 3-inch biscuit cutter to cut 1 round from each stack; use 1/2-inch biscuit cutter to cut small hole in center of each round. Reroll remaining dough to cut third doughnut.
Fry doughnuts in hot oil 1 1/2 minutes on each side or until deep golden brown and cooked through.
Drain on paper towels. Cool 5 minutes.
Carefully split doughnuts in half.
Place marshmallow creme in resealable food-storage plastic bag.
Cut 1/2 inch off one corner of bag; pipe marshmallow creme onto bottom half of each doughnut. Cover each with top of doughnut.
