Lemon Poppy Seed Cake

You know that feeling where you feel like you have so much to share that you don't know where to begin? That's kinda how I feel right now. Like this cake right here! I made it for a friend's baby shower last week. She and her hubby picked the flavor and the overall design/deco direction. After testing a few different recipes, I decided to adapt this Orange Poppy Seed Marimekko Cake recipe from the ridiculously talented Sprinkles Bakes and ended up loving it so much that I went ahead and made an extra cake to take to a DIY grilled pizza party with friends (aka adult pizza party) later that day! I topped it with some fresh lemon slices and felt like the bright, cheery, sunny citrus totally made this cake look extra happy while lending that little touch of elegance. The cake that went to the shower was topped with the cutest flag topper ever, made by my awesomely talented friend, Rachel

A bit about the cake. The crunchy poppy seed to soft, light cake ratio is perf (in my opinion) but if you're a HUGE poppy seed fan, add another tablespoon. Also, the lemon filling (let's be honest, it's pretty much a lemon jelly) is mouth puckeringly tart with just enough sweetness to balance out that sour lemon flavor but if you like things on the sweet side, please add an extra tablespoon or two (up to 1/4 cup) of granulated sugar. Finally, while the lemon is very subtle in both the cake and the buttercream frosting, I promise you'll get a punch of zippy lemon from the lemon filling, so please, please, please do not skip it. Last but not least, if you're looking to replicate the line design on the finished cake, here's a tip: frost the cake and smooth as you typically would, then run a narrow/small offset spatula along the bottom of the full circumference of the cake, applying a bit of pressure to make your first set of lines. Next, line up the lower edge of the spatula up with the top line you just created and run it along the full circumference again. Repeat until the sides are done then switch to the top. Start from the outer edge then work your way in. As for the lemon slices, use a sharp knife to get those thin slices and decorate as you please!

Lemon Poppy Seed Cake

Slightly adapted from Sprinkles Bakes and this frosting 

Makes One 3-Layer 9" Round Cake

INGREDIENTS

CAKE

  • 1 1/2 c. granulated sugar
  • 3 large eggs, room temperature
  • 1/2 c. vegetable oil
  • 1 c. full-fat sour cream
  • 1 tsp. vanilla extract
  • Zest of 3 lemons (about 2 tablespoons)
  • 2 Tbsp. poppy seeds
  • 3 1/2 c. cake flour
  • 1/4 tsp. kosher salt
  • 3 tsp. baking powder
  • 1 1/3 c. buttermilk

LEMON FILLING

12 oz. peeled and quartered fresh lemons (about 6-7 large lemons)
3/4 c. filtered water
1/2 c. + 2 Tbsp. granulated sugar
2 Tbsp. cornstarch
Pinch of kosher salt

LEMON BUTTERCREAM

  • 16 oz. (1 c.) unsalted butter, softened
  • 1 tsp. (clear) lemon extract
  • 3 - 4 c. powdered sugar, sifted
  • 2 - 4 tsp. milk (I used almond milk)
  • Pinch of kosher salt

TOOLS

  • Three 9" x 2" round cake pans
  • Three 9" parchment rounds
  • Stand mixer
  • Mixing bowl
  • Whisk
  • Small heavy-bottomed saucepan
  • Silicone spatula
  • Measuring cups and spoons
  • Wire cooling rack
  • Plastic wrap
  • Offset spatula
  • Piping bag fitted with tip
  • Sharp knife to level cakes

FIX

CAKE

  1. Move racks to middle of oven and preheat to 325°. Butter three cake pans and line with parchment rounds. Butter the rounds then dust pans with flour. Tap out any excess flour and set aside pans.
  2. In the bowl of stand mixer fitted with paddle attachment, combine sugar, eggs, and oil and beat on low speed until combined. Add sour cream, vanilla, lemon zest, and poppy seeds and mix until well combined. Sift in 3 cups of the flour, the salt, and baking powder and mix on low until just combined. Add buttermilk and mix until incorporated. Scrape down edges of the bowl with a silicone spatula. Sift in the remaining 1/2 cup of flour and mix until combined. Scrape down the bowl and beat again briefly.
  3. Evenly distribute batter amongst the three prepared pans. Bake for 24-27 minutes. Test doneness with a toothpick inserted into the center of the cake. If it comes out clean, the cake is done! Cool in pans for 5 minutes, then invert onto a rack to cool completely. When cooled completely, wrap tightly in plastic wrap and transfer to freezer till ready to frost. 

LEMON FILLING

  1. In a small saucepan, bring the peeled and quartered lemons and water to a boil. Mash them as they cook with the back of a wooden spoon. Reduce heat. Simmer for 5 minutes. Remove from heat. Press lemons through a sieve; discard membranes and seeds and allow the mixture to cool. You should have 1 cup of cooked juice, if you’re short, fill the measure with fresh squeezed lemon juice until it reaches 1 cup.
  2. Wash and dry the saucepan to reuse. Combine the sugar and cornstarch in the pan; stir in the cooled lemon juice mixture and whisk until smooth. Bring the mixture to a boil and cook for 2 minutes or until thickened. Transfer the mixture to two small bowls, dividing evenly, and let cool completely.

LEMON BUTTERCREAM

  1. In the bowl of stand mixer fitted with paddle attachment, combine unsalted butter and lemon extract and beat on medium-low speed until for 2-3 minutes. Add 3 c. powdered sugar and salt and beat at low speed until combined. Once combined, increase speed to medium and beat for around 3 minutes, or until light and fluffy. Add 2 tsp. milk and beat for another minute. If you'd like a thicker consistency, add more sugar. If it needs to be thinned out a bit, add more milk. 

FROSTING THE CAKE

  1. Level off your cake layers (if necessary). Set your first cake layer on a plate with flat side facing down. Pipe a border of buttercream around the edge of your layer then fill with one of the two small bowls of lemon filling. Top with the second cake layer, flattest side up. Repeat the piping and lemon filling and finish with third layer. Using your offset spatula, frost cake with the remaining buttercream and decorate as you please! Note, you can do a thin crumb coat with the buttercream, refrigerate for at least 30 minutes then cover with an additional layer of buttercream if you'd like but I didn't. Refrigerate for at least an hour before slicing. 
  2. Serve and enjoy!