Preheat oven to 375°F. Line a 10x15" jelly roll pan with parchment paper and grease well. Set aside. Fold a cotton tea towel into a rectangle slightly larger than prepared pan. Lay on a flat surface and dust the top liberally with powdered sugar.
In a large bowl whisk eggs and granulated sugar together until thick. Beat in sweet potato and whisk to incorporate.
Sift flour, baking powder, baking soda, cinnamon, cloves and salt together then add to egg mixture. Stir just until combined.
Pour batter into prepared pan. Sprinkle evenly with chopped nuts, if using.
Bake in preheated oven for 13-15 minutes or until center of cake springs back when lightly touched. Remove from oven and immediately invert cake onto a prepped towel. Peel off the parchment paper and roll up the cake and towel together starting with the shorter side of the cake.
Let cool on a wire rack then transfer to the fridge to cool completely.
Beat cream cheese, powdered sugar and vanilla together until smooth and airy.
In a separate bowl whip cream on high speed until stiff peaks form. Transfer whipped cream to cream cheese mixture and g-e-n-t-l-y fold together just until combined.
Carefully unroll cake and spread the filling evenly over entire cake. Re-roll just the cake and filling peeling away from the towel as you go. Wrap in plastic wrap and chill in fridge for several hours or overnight until completely chilled.
Cut into 10 1-inch slices and serve cold or slightly cooler than room temperature.