Spray a 9x13" pan with cooking spray. Preheat your oven to 350 degrees.
Whisk together melted butter and sugar in a large mixing bowl. Whisk in the vanilla and eggs. Stir in flour, cocoa powder, and salt.
Spread batter in the prepared pan. Bake at 350° for about 30 minutes, or until a toothpick comes out with moist crumbs, but no batter. Cool completely.
Topping:
In a mixing bowl, beat the pudding mix and milk till smooth, set aside.
In a glass bowl, beat the whipping cream till soft peaks form. Beat in the powdered sugar and vanilla. Set aside about a cup of the whipped cream.
Whisk the remaining whipped cream and pudding together till smooth. Set aside.
Arrange the sliced bananas in an even layer over the brownies. Spread the pudding/cream mixture over the top of the bananas. Make sure you go all the way to the edge of the pan, making a tight seal, so the bananas don't brown as quickly. Cover and chill for at least 30 minutes, or till set.
Cut into squares and garnish each serving with a dollop of whipped cream, chopped strawberries, and peanuts.
Notes
You can use a brownie mix if you prefer. Just make sure you use one that makes a 9x13" pan of brownies.