In a stand mixer or using a hand mixer, combine the Dream Whip packet and 1/2 c of milk. Blend for 4 mins or until firm peaks form. Using a rubber spatula, transfer whip to another bowl. Using the same bowl but empty bowl, whip heavy cream until medium/firm peaks form. Add vanilla or other flavorings if desired, but not necessary. Transfer the Dream Whip to the bowl with the whipped cream and fold gently until completely incorporated. This will stabilize the whipping cream. Cover and refrigerate until ready to use.