In a stand mixer with the paddle attachment, beat the cream cheese and butter together on medium speed until completely smooth and homogenous. No streaks, no lumps.
Sift the cocoa powder, kosher salt, and powdered sugar directly into the bowl. Mix on low speed until combined. Scrape down the sides of the bowl.
Mix in the vanilla extract. Taste and adjust if needed.
Switch to the whisk attachment and beat on medium-high until it is lightened and fluffy, about 2 minutes.
Optional: Make it whipped. For an even lighter frosting, add ¼- ½ cup of cold heavy whipping cream and beat everything until stiff peaks form. This creates a frosting that pipes beautifully and has an almost mousse-like texture.
Notes
Yield – About 3 cups of frosting (enough to frost 24 cupcakes or 1, 9x13 pan) Flavor Tips – For a rich chocolate flavor, use Dutch-processed cocoa powder! Variations – Like with this peppermint frosting, you can add ¼ teaspoon of peppermint extract along with the vanilla. Start small—peppermint is potent. Storage – Store in a clean, airtight container in the refrigerator for up to 3 weeks or in the freezer for up to 2 months.