Preheat oven to 350 degrees. Line a 9-inch square baking dish with aluminum foil or parchment paper, allowing edges to extend over sides of pan. Spray with nonstick baking spray with flour.
In a large bowl, stir together sugar, flour, cocoa powder, salt, vegetable oil, eggs, and vanilla extract until well blended. Stir in 1/2 cup Andes baking chips.
Pour batter into prepared pan. Bake for 25-30 minutes, or until a wooden pick inserted in center comes out clean. Let cool completely.
For Peppermint Cream, combine white chocolate chips, 1 cup Andes baking chips, and heavy cream in a medium heavy-bottomed saucepan. Place over low heat and stir continuously until melted and smooth. Pour over brownies. Refrigerate for at least 1 hour.
For Chocolate Glaze, combine chopped chocolate and butter in a heavy-bottomed saucepan. Heat over low heat, stirring continuously, until smooth. Remove from heat and whisk in vanilla, powdered sugar, and milk. Whisk until smooth and then pour over Peppermint Cream layer. Let set before slicing into squares.