In a large bowl, whip heavy whipping cream until firm peaks form. Spoon into separate bowl and set aside.
In the same bowl you just whipped the cream in, stir pumpkin, ricotta, sugar, cinnamon, nutmeg and vanilla together. Scrape sides and whip 1 minute. Carefully fold in whipped cream.
Spoon or pipe into sugar cones and top with chocolate chips and walnuts. Serve.