To prepare cookies, combine sugar and flour, stirring with a whisk. Add vanilla and egg; beat with a mixer at medium speed 2 minutes. Cover and refrigerate 2 hours.
Preheat oven to 350°.
Cover a large baking sheet with parchment paper. Draw 6 (3-inch) circles on paper. Turn paper over; secure with masking tape. Spoon about 1 tablespoon batter into center of each drawn circle; spread batter to outside edge of each circle. Bake at 350° for 6 minutes or until edges begin to brown. Carefully remove cookies from paper, and cool completely on wire racks. Repeat procedure with remaining batter, reusing the parchment paper.
To prepare filling, combine ice cream and banana in a chilled bowl, stirring well. Place 1/4 cup peanuts in a shallow bowl. Place 1 cookie on each of 6 plates. Carefully spread about 1/3 cup ice cream mixture over flat side of each cookie. Top with remaining cookies, flat sides down, pressing gently. Lightly roll the sides of each sandwich in peanuts.
Top each sandwich with 1 tablespoon whipped topping, 1 tablespoon chocolate syrup, remaining 1 teaspoon peanuts, and 1 cherry. Serve immediately.