Make Hot Fudge Sauce and chill at least 2 hours. (This can be made several days ahead, if desired). Bake brownies according to package directions. Cool. Measure 2 cups coarsely cubed brownies and refrigerate until ready to make the ice cream. The remaining brownies can be enjoyed anytime.
Combine milk, cream and sugar in a mixing bowl and stir well to dissolve the sugar. Add corn syrup, vanilla extract and salt; continue stirring until well blended.
Pour mixture into ice cream machine bowl. Process according to manufacturer directions for 25 to 30 minutes or until the consistency of thick soft-serve ice cream. Add cubed brownies the last 2 to 3 minutes of churning. Immediately pour into a large bowl and freeze 1 hour. The ice cream will become more solid in the freezer.
Layer ice cream and chilled Hot Fudge Sauce in a freezer container. Freeze at least 2 hours before serving.
**Or, prepare your favourite brownie recipe.