This Meyer lemon and poppy seed layer cake — with roasted rhubarb and thyme compote — delivers a pastel-colored dessert that is as fresh and delicate as an early spring morning.
STORY AND PHOTOS BY PAOLA THOMAS
The days are lengthening, the cherry trees are burgeoning and tender green shoots are peeking through the dirt. This cake delivers all the, pastel-colored prettiness we crave at this time of year and would make a stunning addition to your Easter table.
The tartness of rhubarb makes it a great complement to lemon, as it provides a similar counterpoint to anything sweet. I made a simple roasted-rhubarb and thyme compote and used it both as a filling and stirred into an ethereal mascarpone frosting to enliven a lemon and poppy seed cake with layers of rhubarb flavor. The result is a cake as fresh and delicate as the first rays of sunshine on a spring morning.
The good news is that this cake works equally well with fresh or frozen rhubarb, and if you can’t get Meyer lemons, ordinary lemons will be just as good.
Makes 1, 4-layer, x 7- inch cake | Serves: 8–-10 | start to finish: 2 hours, including baking and cooling time (active time: 40 minutes)
First, make the compote.
For the roasted rhubarb and thyme compote
- 2 pounds fresh or frozen rhubarb, cut into 2-inch pieces
- 1 tablespoon fresh thyme leaves, stripped from their stems
- 1/2 cup brown sugar
- Zest and juice of one lemon
Preheat oven to 350°F. Place the rhubarb pieces in a large oven-proof pan. The pan should be big enough to accommodate the rhubarb pieces in a single layer and have sides at least 1 inch deep so that the juices are retained.
Sprinkle the rhubarb with thyme, brown sugar, and lemon zest and juice. Stir so that the rhubarb pieces are evenly coated with the sugar and flavorings, and bake for approximately 40 minutes until the rhubarb is very soft and juicy and collapses when stirred with a spoon. There is no need to defrost frozen rhubarb, but if using, you will need to roast it approximately 10 minutes longer. When the rhubarb is cooked, stir the pulp and juices together until you have a thick compote. Set aside to cool.
While the compote is in the oven, you can start making the cake — or you can make the compote ahead of time. It will store happily in the fridge for about a week.
For the lemon poppy seed cake
- Olive oil for greasing the pans
- 1 cup granulated or baker’s sugar
- Zest and juice from 4 Meyer lemons or 2 large ordinary lemons
- 1 cup all-purpose flour
- 1/2 cup almond flour
- 1/2 teaspoon salt
- 1/2 teaspoon baking powder
- 1/2 teaspoon baking soda
- 2 tablespoons poppy seeds
- 1/2 cup buttermilk
- 1/2 cup mild extra-virgin olive oil
- 2 large eggs
- 1/2 teaspoon vanilla extract
Brush olive oil over the bottoms and sides of two 7-inch x 2-inch layer pans and line them with a circle of parchment paper.
Preheat oven to 350°F.
Combine sugar and lemon zest in a large bowl, rubbing the zest into the sugar with your fingers to release the oils. Stir in the flour, almond flour, salt, baking powder, baking soda, and poppy seeds until fully combined. Set aside.
In a second bowl, whisk together the lemon juice, buttermilk, olive oil, eggs, and vanilla extract.
Pour the wet ingredients into the dry ingredients and stir together until everything is fully combined. You should have a slack, but not entirely liquid, batter.
Divide the batter evenly between the two cake pans (weigh them if perfectly even layers are important to you) and then place in the oven.
Bake for approximately 40 minutes or until golden brown, firm to the touch, and starting to shrink away from the sides of the pans.
Cool the cakes in the pans for 5 minutes, then use a knife to loosen the sides, and flip the pans onto a wire rack. Allow the cakes to slide out of the pans and remove the lining papers. Cool thoroughly on a wire rack.
For the mascarpone frosting
- 1 8-ounce pack mascarpone cheese (or use ordinary cream cheese)
- 1/4 cup powdered sugar, sifted
- 1 cup heavy whipping cream
- 1 teaspoon lemon juice
Using either a stand mixer or hand mixer, place the cheese and sugar into a bowl and stir together to loosen the cheese. Add the cream and lemon juice and beat everything together 2–3 minutes until stiff peaks have formed. The cheese and sugar stabilize the cream so it will remain whipped and creamy, even in warm weather.
To assemble the cake
Cut each cake layer in half through the middle to form a total of four layers.
Pass at least four tablespoons of rhubarb compote through a sieve or food mill to remove the fibers. Using fibrous compote is fine to fill the cake, but you will want to use smooth compote in the outside frosting.
Spread three of the cake layers with a layer of compote and a layer of mascarpone frosting. Stack the layers and finish with the final cake layer.
Stir approximately 4 tablespoons of sieved compote into the remaining frosting, making sure the frosting doesn’t get too slack.
Swirl the rhubarb and mascarpone frosting over the stacked cake layers.