In a small saucepan, combine the milk and melted chocolate chips over low heat until heated through, smooth and creamy.

In another small saucepan, combine the peanut butter and corn syrup and heat over low heat until heated through, smooth, and creamy. Add the butter and vanilla and stir to combine. Remove from the heat. (Alternatively, combine peanut butter and corn syrup in a microwaveable bowl and microwave, stirring periodically, until smooth, creamy and hot.)

Divide the crumbled brownies evenly between 6 sundae glasses or ice cream coupes and sprinkle the sliced bananas over the brownies. Then spoon about 1/3 cup of the peanut butter sauce over the bananas and spoon about 1/3 cup of the chocolate sauce on top of the peanut butter sauce. Top with a large scoop of vanilla ice cream into each glass. Top with a splash of brandy, if using, and a dollop of whipped cream, if using. Sprinkle the top of each with some of the crushed peanuts. Top each sundae with a maraschino cherry and serve immediately.