In a large bowl, whisk together the heavy cream, whole milk, granulated sugar, and vanilla extract. Mix until the sugar is fully dissolved and the ingredients are well blended.

Gently fold in your favorite mix-ins, such as chocolate chips or fruit chunks, to maintain a light and airy texture.

Cover the bowl with plastic wrap and refrigerate the mixture for at least 2 hours.

Once chilled, pour the mixture into the Ninja Creami container and secure the lid tightly.

Select the 'ice cream' setting on your Ninja Creami. Let it churn until the mixture reaches a creamy consistency, which usually takes about 30 minutes.

Enjoy your creation immediately for a delightful soft-serve experience, or refreeze it for a firmer texture.