Place bananas on a sheet pan. Bake at 350° for 20 minutes. Remove 1/2 of the bananas; cool completely. Peel and cut into 1/2-inch-thick slices.
6 each bananas
Bake the remaining bananas at 350° for an additional 20 minutes. Carefully peel and place the bananas in a blender, and blend until smooth.
Cook the custard
Combine milk and 1/2 of the sugar in a saucepan over medium-high heat. Bring to a simmer. Combine the remaining 1/2 amount of sugar, cornstarch, salt, and eggs in a medium bowl; stir well with a whisk. Gradually add hot milk mixture to the mixture, stirring constantly with a whisk. Return milk mixture to pan. Cook for about two to three minutes over medium heat until thick and bubbly, stirring constantly.
8 ounce milk, 4 ounce sugar, 2 each eggs, 2 tbsp cornstarch, 1/4 tsp salt
Add blended bananas, butter, and vanilla, stirring until butter melts. Chill the mixture, stirring occasionally. Add sliced bananas, mix and fold 2/3 of the whipped topping into the pudding