Lemon Poppy Seed Rhubard Upside-Down Cake: A Piece of Cake #22

Calling all 'barbz! (Rhubarbs, that is.)

It’s barb season baby, rhubarb that is. And what a wonderful season it is. Rhubarb at the greenmarket means we’ve turned the corner on frosty nights, and summer is on its way, officially. And to celebrate, this month’s snack cake obviously needed to be rhubarb. Why not combine it with another seasonal fave? Lemon poppy seed. 

I love an upside-down cake for its versatility, and this recipe will be a great addition to your arsenal all year long. Sure, I wrote this recipe for rhubarb season. But wouldn't it be great with blackberries in July, or peaches in August, or PLUMS as soon as you can get your hands on them? Honestly, I can’t think of a fruit that would be bad in an upside-down cake. It’s fruit, cooked in caramel, with cake baked on top. It bakes for a really long time, so you don’t need to precook the fruit. You can’t mess this one up that much. But you can mess your oven up! Definitely place your cake pan on a sheet tray, in case that fruit bubbles over. 

You can even omit the poppyseeds, and or lemon if you want. Add vanilla or lime zest to pair with pineapple or a little cardamom with a peach upside-down cake. You can either toss dry spices with the fruit or add them to the cake batter. And any variety of extracts could be subbed in for the lemon juice; just trust your gut. Take this base cake recipe and play with it. (Or stick to it! It’s really good!) Let me know what you come up with.

Lemon Poppy Seed Rhubard Upside-Down Cake

For the rhubarb: 

¾ pound rhubarb, cut into ½ inch chunks about 2 cups

⅓ cup granulated sugar

1 ½ teaspoons corn starch

For the cake: 

1 cup all-purpose flour

1 ½ teaspoons baking powder

1 teaspoon Diamond Crystal kosher salt

2 tablespoons poppy seeds

5 tablespoons unsalted butter, room temp

1 cup granulated sugar

Zest of one lemon

2 eggs

1 egg yolk

3 tablespoons canola oil

2 tablespoons lemon juice

½ cup whole milk

For the caramel:

⅓ cup brown sugar

3 tablespoons unsalted butter

Pinch of salt

  1. Toss the chopped rhubarb with the sugar and cornstarch in a medium bowl. Set aside.

  2. Whisk together the flour, baking powder, salt, and poppy seeds in a small bowl. 

  3. In a stand mixer fitted with a paddle, cream the butter, sugar, and lemon zest until light and fluffy. Add the eggs and yolk, one at a time, until well-combined. Scrape the sides and bottom of the bowl. Beat until well-combined. 

  4. Add in the oil, and beat until combined. Add the lemon juice, and beat until combined. 

  5. Add the flour in two additions, alternating with the milk. Mix on low until combined. Scrape the sides and bottom of the bowl, and mix again to combine. 

  6. Melt the butter in a skillet and whisk in the brown sugar and salt. Cook until bubbling, then remove from heat. 

  7. Grease a 9-inch cake pan with pan spray. Pour the brown sugar/butter mixture into the greased pan, and spread to cover the bottom. Evenly distribute the rhubarb over the brown sugar mixture, including any juices that have accumulated. 

  8. Scrape the cake batter into the pan and spread to completely cover the rhubarb. Place the pan on a sheet tray. 

  9. Bake at 350 degrees for 1 hour to 1 hour & 15 minutes, until a toothpick comes clean from the cake. 

  10. Cool for 5 minutes in the pan. Run a knife around the edge of the cake, releasing the cake from the pan. Place a plate upside down on the cake pan, and in one swift motion, flip the cake pan and plate right-side up. Gently lift the cake pan off the cake. Scrape any remaining caramel and rhubarb stuck in the pan back onto the cake. Serve warm with vanilla ice cream. At least, that's what I did, and it was lovely.

Quick Bites: 

  • This Saturday, May 8th, Jono Pandolfi is having a tent sale at their Union City, NJ studio. You know I love their stuff, so you’ll see me there! I’m driving back for this one. Make a reservation here

  • Have you seen the trailer for High on the Hog, coming out on Netflix this month? It’s based on Jessica B. Harris’ book, High on the Hog: A Culinary Journey from Africa to America, and it looks incredible.