Nutrition information is calculated using an ingredient database and should be considered an estimate
Preheat oven to 350°. Grease 9 x 5-inch loaf pan with additional I Can't Believe It's Not Butter! and set aside.
Combine I Can’t Believe It’s Not Butter! and brown sugar using an electric mixer on high speed. Beat until mixture is creamy and fluffy. Scrape bowl often using a rubber spatula. Add eggs one at a time, followed by vanilla. Continue to beat until fully blended. Reduce mixer speed to low and slowly add flour, baking soda, cinnamon, and salt to mixer bowl. Mix until just combined. Stir in mashed bananas.
Bake 1 hour to 1 hour 10 minutes until toothpick inserted in center comes out clean. Cool 20 minutes on wire rack; remove from pan and cool completely.
Remove the center of the cooled bread with a large knife, leaving a 1'' border along the bottom and all sides. Set aside the center piece that was removed. This will be the lid of the bread.
Fill the hole in the banana bread with ice cream. Use the back of a spoon to push ice cream into the nooks and crannies in the bread. Trim the reserved lid and put it on top of ice cream. Freeze the assembled bread overnight.
Place in the fridge to defrost about 30 minutes before serving.