Sponge Cake
- 3 large eggs at room temperature
- 1/4 cup granulated sugar (60 g)
- 1/2 tsp vanilla extract
- pinch salt
- 1/2 cup all-purpose flour (70 g) or cake flour, plus a little for dusting
- butter for greasing the pans
Lavender-Lemon Syrup
- 1/2 cup sugar
- 1/2 cup water
- 1/4 tsp lavender
- 1/4 cup lemon juice
Semifreddo
- 1 cup cream
- 1/2 tsp lavender
- 1 tsp sugar (optional – see instructions)
- 4 large eggs at room temperature
- 2 tbsp lemon zest (approx 2 lemons)
- 1/4 cup lemon juice
- 1/2 cup honey or 1/2 cup + 1 tbsp sugar
- 1/8 tsp salt
Instructions
Sponge Cake
- Line two 8 inch cake pans with a circle of parchment paper. Grease the sides and paper with a bit of butter, and dust with flour.
- Preheat your oven to 350°F (176°C), and position the racks so that the cakes will sit in the middle.
- Note: these instructions are for a stand mixer. If you’re using a hand mixer, see the notes below for the variation. In an electric stand mixer with a whisk attachment, beat the eggs at high speed for about 1 minute, then add the sugar slowly. Add the vanilla and salt. Continue to whip at high speed for 5 minutes. The resulting mixture should be airy, light yellow, and have the sugar well-dissolved. If you see a lot of grains of sugar, or the mixture isn’t looking very airy, continue to whip for another 2-3 minutes.
- Sift the flour into the egg and sugar mixture slowly, stirring gently with a spatula to combine without deflating the whipped eggs. Stir just enough to incorporate the flour into the batter, taking care to get the spatula to the bottom and edges of the bowl to avoid leaving any clumps.
- Divide the cake batter between the two pans. Bake in the center of the oven for approximately 20 minutes, or until the top is golden and a toothpick emerges clean. Carefully remove the cakes from their pans, before transferring them to a rack to cool. You can keep one of the parchment paper rounds to re-line the pan for the freezer step (see below). When cooled, finish with lavender-lemon syrup (see next step).
Lavender-Lemon Syrup
- Combine the sugar, water, lemon juice, and lavender in a small saucepan. Heat over low on the stove top, keeping the mixture just below a simmer for about 5 minutes. Set aside to cool for at least 10 minutes (note that you can also make and refrigerate the syrup ahead of time).
Semifreddo
- Whip the cream until it forms stiff peaks, then set aside. Clean and dry the mixer bowl. Note that this step can be done the day before to save time.
- Optional – Place the lavender and sugar together in a spice grinder or mortar, and grind together to make a fine lavender/sugar powder, then set aside. You can sift out any larger pieces with small strainer. If you don’t mind whole lavender flowers in the semifreddo then you can skip this step and omit the extra tablespoon of sugar.
- Set up double boiler on the stove. I simply float the stand mixer bowl in a large pot (Dutch oven) filled 2/3rds of the way with water, but anything large enough to easily accommodate your bowl. Heat the water but keep well below a boil.
- Add eggs, honey, lemon juice, zest, lavender/sugar, and salt to the clean and dry stand mixer bowl, or another large metal bowl if your mixer bowl won’t sit comfortably on a double boiler. Mix together.
- Place the bowl on the double boiler. Gently whisk the ingredients to keep them moving (this will keep the egg from scrambling). Cook until the temperature of the mixture reaches 165°F (74°C) – about 5-7 minutes. It should look thick and glossy, but still be quite runny.
- Transfer the mixture to the stand mixer and whip with the whisk attachment until the mixture is airy and approximately quadrupled in size (about 5 minutes, but this will vary a bit depending on your mixer, and take longer if you’re using a hand mixer).
- Gently fold the whipped cream into the mixture with a whisk or a spatula. Mix just enough to incorporate all the ingredients while taking care not to deflate things.
To Assemble
- Place one of the parchment paper rounds back into a cake pan. Take a long (26 inch/66 cm minimum) sheet of aluminum foil and fold it in half the long way, then shape it into a round wall lining the cake pan. This will act to extend the walls of the cake pan upward, allowing you to make the semifreddo cake taller. Gently slide one cake into the pan (doing this last will help to hold the foil in place).
- Brush about 1/3 of the syrup over the cake in the pan. Set the remainder aside.
- Pour the finished semifreddo over the bottom cake layer. Tap gently to remove any air pockets.
- Gently place the second cake over the semifreddo. Brush the top of this cake layer with another 1/3 of the syrup. Transfer the cake to the freezer and freeze for at least 8 hours.
To Serve
- Remove the cake from the freezer and gently pull out the aluminum foil lining. Lift or turn the cake out of the pan carefully (it may help to let it thaw for a minute or two if the semifreddo is frozen to the pan. Remove the parchment paper lining.
- Allow the cake to sit for about 3-4 minutes to soften a little. Garnish with lavender flowers or a dusting of powdered sugar. Slice with a large, thin knife that’s been dipped in warm water.
- Optional: take the remaining lemon/lavender glaze and mix it with 1 tbsp of honey. This is a bit easier to do if you heat the honey first (10 seconds in the microwave should do it). This can be drizzled over the cake, or on individual slices.
Recipe Notes
No Stand Mixer? Read On!
Given the huge amount of whipping needed to properly aerate both the cake batter and the semifreddo, this is definitely an ideal stand mixer recipe, but if you only have a hand mixer you can make this work with a little modification. If you have a whisk and arms like Thor, you can probably even do it by hand.
Whipping whole eggs is tricky, which is why we let the stand mixer do all the work. If you’ve got a hand mixer you can achieve a similar effect by separating the whites and yolks for both the cake and semifreddo components and whipping them separately.
Note that the instructions below are designed to interweave with the primary instructions above, so be sure to read everything carefully.
For the cake: whip half of the sugar with yolks until they form a light yellow, foamy mixture. Whip the remaining sugar with the whites until ‘trails’ form in the whites (i.e. lines left by the whisk don’t disappear back into the foam). Combine everything together (gently to avoid deflating things) and bake as instructed in the basic recipe above.
For the semifreddo: as with the cake, you want to separate the yolks and the whites and whip them separately. If you’re using honey you won’t have to worry about getting all of the sugar to dissolve, so that simplifies things a bit. Stir the yolks with the honey, lemon juice/zest, lavender/sugar, and salt over a double-boiler/bain-marie (as above) until the mixture reaches 165°F (74°C), then set aside to cool slightly. Whip the egg whites to stiff peaks and set them aside as well, then whip the cream and set it aside. Lots of whipping. Lastly, whip the cooked semifreddo mixture to an airy foam; about four times the original volume. Carefully combine the three whipped mixtures, stirring gently until just combined, and freeze between the cakes as instructed in above.