Grease a 10x15 baking pan and line with parchment paper (you want the paper coming all the way up the sides. You are going to have to use it to lift the cake out of the pan) then grease the paper. Set aside.
Preheat your oven to 375 degrees.
In a large bowl with a hand mixer at high speed, beat the eggs for 2-3 minutes until foamy. Gradually add in sugar. Stir in the pumpkin, vanilla and lemon juice.
In a small bowl, stir together the flour, baking powder, salt and spices. Add the flour mixture to the pumpkin mixture and stir until everything is combined and moistened. Pour the batter into the prepared pan and bake for 12-15 minutes.
The key here is to bake this cake until it is just done. You do not want to overcook this cake or it won’t roll up very well.
Let the cake cool for 5 minutes then, using the parchment paper as a lift, gently remove the cake from the pan and set on a work surface. You want to then slowly and carefully roll up the cake (keep the paper on. You even want it rolled up inside the cake so it doesn’t stick to itself) from the narrow end. Let the cake cool in a rolled position for another 15 minutes.
Beat the filling ingredients together until smooth then gently unroll the cake. Do not freak out if it cracks a little. You will “glue” the cracks together with the filling. Spread the filling onto the inside of the unrolled cake in an even layer, then gently roll the cake back up. Wrap the roll snugly in the parchment paper and refrigerate for 2 hours. Dust the cake with powdered sugar, slice and serve!