Ube chiffon cake

Instructions

1. Step 1

   Heat the oven to 160°C with a rack one level below the middle, and set a dry 20 cm tube pan ready nearby. An oven at the right temperature keeps the deep purple batter from scorching on top before the inside is baked. You can use an oven thermometer to be sure the oven has reached temperature.

   Mark step 1 as done

2. Step 2

   Put 90 g ube jam and 65 g coconut milk in a small saucepan, stir over low heat for about two minutes, then turn off the heat and let it cool. The gentle warmth loosens the thick, sticky ube jam so it blends into the coconut milk. The mixture is ready when it's smooth, as thick as a sauce and free of lumps of jam.

   Low heat.

   Mark step 2 as done

3. Step 3

   Whisk 90 g egg yolks with 15 g granulated sugar and a pinch salt, then pour in 45 g vegetable oil and the cooled ube mixture and stir until well combined. Wait for the ube to cool so the yolks don't cook into lumps. The mixture is ready when it's an even deep purple and glossy.

   Mark step 3 as done

4. Step 4

   Sift 90 g cake flour with 2 g baking powder over the top and whisk slowly until all the flour is moistened. Sifting makes the flour fall in a fine, loose shower and dissolve quickly, so you don't have to whisk for long. The mixture is ready when it's smooth as cream with no white specks of flour.

   Mark step 4 as done

5. Step 5

   Start beating 165 g egg whites with 1 g cream of tartar on low speed, and once the foam turns fine, add 65 g superfine sugar in three additions and gradually raise the speed, for about seven minutes in total. Increasing the speed slowly creates small, even bubbles that hold up better when mixed with the heavy ube batter. The meringue is ready when it's as smooth as shaving cream and the peaks curl slightly.

   Suggested time: about 7 minutes.

   Mark step 5 as done

6. Step 6

   Divide the meringue into thirds, vigorously whisk the first third into the ube bowl to loosen it, then fold in the other two thirds gently from the bottom up, turning the bowl after each stroke. The ube mixture is fairly heavy, so adding the meringue in portions helps keep the batter airy. The batter is ready when the purple is evenly spread with no white streaks and a ribbon of batter rests on the surface for a moment.

   Mark step 6 as done

7. Step 7

   Pour the batter into the tube pan in one continuous stream, shake it gently to level the top, then bake at 160°C for about 45 to 50 minutes. A low temperature and long bake keep the cake's purple bright instead of turning brown. The cake is done when the top is dry, springs right back when pressed and a skewer comes out clean.

   Bake at 160°C for about 45 to 50 minutes.

   Mark step 7 as done

8. Step 8

   As soon as it comes out of the oven, turn the pan upside down onto a narrow-necked bottle and let the cake hang like that for about an hour and a half. The crumb's structure only sets once fully cool, and hanging it upside down keeps it from collapsing under its own weight. The cake is cool enough when the whole pan has reached room temperature.

   Suggested time: about 90 minutes.

   Mark step 8 as done

9. Step 9

   Run a knife closely around the side of the pan and the center tube to release the cake, set it on a plate and slice it with a serrated knife, sawing gently back and forth instead of pressing down hard. A serrated knife keeps the soft air pockets intact so the crumb isn't squashed. The slices are just right when they're straight, with an airy purple crumb that doesn't stick to the blade.

   Mark step 9 as done