In a large bowl, add in the 4 ounces cream cheesee. Using a hand mixer, beat on medium speed until smooth. Scrape down the sides of the bowl.
Add in the 1 cup heavy whipping cream and continue to beat until soft peaks form.
Add in the 1/2 cup powdered sugar and 1 teaspoon vanilla extract. Beat until stiff peaks form. The whipped cream will be able to hold its shape without falling over.
Add the whipped cream to a piping bag fitted with a piping tip and pipe onto a cake, cheesecake, cookie, etc. You can also use a butter knife or angled spatula and just spread it on.
Notes
To make a layered cake, I recommend doubling the recipe. Storage: Store covered with plastic wrap or in an airtight container in the fridge for up to 5 days. Freezing: Place in a freezer-safe container and store in the freezer for up to 3 months. Thaw in the refrigerator overnight. You can whip it with your hand mixer on medium speed if it's not as fluffy as you would like.