Add the ricotta to a food processor along with the cream, rosemary, pecorino cheese and season with salt and pepper. Purée until the mixture is smooth and an almost icing-like constituency for about 10-15 seconds.
Transfer the mixture to a piping bag. Pipe the dates with some of the ricotta filling and transfer to a platter. Top with a scattering of the walnuts, a few dusts of fennel pollen if using and a few pinches of flaky salt.