Step 1

Preheat the oven to 370°F (190°C). Line a 11x15 inch baking sheet with parchment paper.

Step 2

On a large piece of parchment paper, generously sprinkle some powdered sugar. We will later invert the cake on this. You can also use a kitchen towel instead.

Step 3

In a small bowl, sift flour, baking powder, salt and cinnamon together and set aside.

Step 4

You will need two large bowls, one for the egg whites and another for the yolks. For the egg whites, it's important that the bowl is super clean and grease free. So pour a little bit of white vinegar into the bowl, swirl around and then empty it out. Wipe the bowl with a clean paper towel. Wipe the whisk attachment with vinegar too. Then, separate the eggs, add the egg whites into the super clean bowl and the yolks into the other. Be careful not to mix in any yolks into the whites.

Step 5

Add ¼ cup granulated sugar to the egg yolks and using an electric hand mixer beat on medium for about 1-2 minutes, until pale and creamy.

Step 6

Add in vanilla extract and pumpkin puree. Mix until combined.

Step 7

Then add in the flour mixture, and mix on low for a few seconds, until just combined (do not over-mix). Set aside.

Step 8

Start beating the egg whites with a whisk attachment on medium high until frothy. Then, while beating, slowly add in the rest of granulated sugar (¼ cup). Once all the sugar is added, continue beating on medium-high until stiff peaks form.

Step 9

Using a spatula, add the egg whites into the batter in 3 parts and fold gently. Be careful not to overmix. The batter will be quite fluffy at the end.

Step 10

Gently transfer the batter into the lined baking sheet and spread it out evenly. You can use an offset spatula to even it out.

Step 11

Bake in the preheated oven for 12-15 minutes. Check by touching the surface, it should gently bounce back.

Step 12

Working quickly, loosen the sides of the cake with a sharp knife. Gently invert the cake onto the dusted parchment paper/kitchen towel (The baking sheet is still hot, so remember to wear oven mitts). Gently peel off the parchment paper from the cake and roll up cake and dusted parchment paper/kitchen towel together, starting from the short end. Let it cool down on a wire rack for about 1-2 hours.

Step 13

Whip the heavy cream and powdered sugar together until soft peaks form. Add in cinnamon and vanilla extract and beat until combined. Taste the filling, add in more powdered sugar if you like it more sweet. Continue beating on high until stiff peaks form. Fold in the walnut pieces if using. Refrigerate until ready to use.

Step 14

Once cake is at room temperature, gently unroll it and evenly spread the filling over it. Reroll the cake, wrap or cover with plastic wrap and refrigerate for at least 1 hour (I think it tastes best the next day!).

Step 15

Once ready to serve, lightly dust with powdered sugar. You can also pipe some more whipped cream on top to decorate. Slice and serve.