Tender grapefruit poppy seed cake, layered with grapefruit curd and cream cheese frosting.
I’m not sure about you, but after that dark chocolate peanut butter cake, I was in need of something light and fruity! I’ve had this grapefruit poppy seed cake on my mind for a while and am so excited I finally had a chance to try it out. This cake originates from a lemon poppy seed cake that I found several years ago and have made nearly a dozen times. The cake and the frosting from the original recipe are light and fluffy, and full of flavor. I have nothing against the original recipe and for a lemon poppy seed cake, it’s my go-to. I simply had the thought to try this cake with grapefruit instead of the lemon, and then add a grapefruit curd since they’re in season and I’m obsessed. Sometimes my ideas are crazy and don’t work out, but this one… it’s a winner!
This cake is really simple to make and can definitely be done in steps. I made the grapefruit curd the day before and stored it in my refrigerator until I was ready to use it. I then made the cake layers the next morning and put it all together later that night. If you’re not going to eat it right away, make sure to cover it in an airtight container and put it in the refrigerator over night. Then let it come back to room temperature before serving.
A quick note about the curd: the color of the grapefruit curd is going to change with each step of the cooking process. When the grapefruit juice is added to the sugar and cornstarch, you get the true grapefruit pink color.
However, once you add your egg yolks, the curd will turn a deep yellow color, like lemon curd. You can certainly use the curd just like this if you want.
If you’d rather the color of the curd better resemble the inside of a grapefruit, just add a little food coloring. I used just a little pink gel and got a vibrant coral color.
As for the vanilla bean, here’s a look at how to cut it open and extract the seeds: slice the vanilla bean down the center and pull apart the two sides to expose the seeds. Use the side of the knife to scrape out the seeds and add it to the ingredients. (Your hands are going to smell amazing after this step!)
I really love how the color of the curd turned out and how it stands out against the white cake and frosting. If you don’t love grapefruit, you can go back to the original recipe and use lemon zest and lemon juice in place of the grapefruit. I’ve also made the original lemon poppy seed cake without curd and it’s fabulous. You really can’t go wrong with this cake.