Chocolate Swiss roll

Heat the oven to 350F and separate the four eggs into two bowls.

Whip the whites with the granulated sugar on high about five minutes to a stiff peak.

Butter the sheet pan, line it with parchment and grease the parchment.

Whip the yolks with the remaining sugar, the oil, the salt and the vanilla two minutes until light and fluffy.

Sift the flour, cocoa powder and baking powder directly into the bowl.

Mix on low only until just combined.

Fold the meringue in in three batches, the first sacrificial, scraping the bottom and cutting through the middle until almost no white streaks remain.

Transfer to the prepared pan and spread it to the edges with an offset spatula in an even, paper thin layer.

Bake at 350F for 12 to 15 minutes until the centre is springy to the touch.

Dust a smooth kitchen towel generously with cocoa powder.

Run a knife around the edge, turn the hot cake out onto the towel in one confident motion and peel off the paper.

Roll it up from the short end, tight but not crushed, and cool on a wire rack about two hours.

Whip the heavy cream, vanilla and powdered sugar from low up to high, finishing by hand at a stiff peak without curdling it.

Scald the half cup of cream in the microwave about 50 to 55 seconds and pour it over the chocolate chips; stand 10 minutes.

Unroll the cooled cake, spread the whipped cream in an even layer into the curl, and roll it back up gently.

Transfer to a wire rack, stir a teaspoon of oil into the ganache until silky.

Brush off the excess cocoa powder, then spoon the ganache over the top and sides.

Set in the fridge before slicing, or transfer while the ganache is still wet.