In a small bowl, whisk together 1/4 cup all-purpose flour, 3 tablespoons natural cocoa powder, and 1/2 teaspoon kosher salt, before adding to the entire mixture. Beat on the mixer's lowest speed for 45 to 60 seconds, until there are no clumps of dry ingredients — but be careful not to overmix! Scrape down the sides of the bowl again, before turning the mixer back on to its lowest speed and streaming in 1/2 cup heavy cream. Continue mixing for an additional 30 to 45 seconds, just until the white streaks of cream are fully mixed in.