Key lime loaf cake

A zesty, creamy, delightful dessert that blends cream cheese, sourdough discard, and fresh limes to create a perfect summer treat.

A few weeks ago I delved into the baking realm of starting (and naming) my very own sourdough starter. Her name is Brunhild and yes, I also agree that she looks like her Germanic/Norse female warrior queen counterpart.

With the creation of a yeast machine comes the responsibility of feeding it at least once a week. With each feeding comes a decent amount of discard that needs to be used or thrown out. I always opt for using it. Typically, I make pizza dough or cinnamon rolls, but wanted to try something new this week. I thought, “why not a cake?” You can make this lovely loaf cake easily without sourdough discard, but if you have some of that gooey goodness lying around, I say try it!

This cake is perfect for a summer evening treat with a hefty side of vanilla ice cream or homemade whipped cream alongside it. Either one would elevate the tartness of the cake.


Cluster of bright green limes, round and gathered together.
  • 1 cup cake flour (add 1/2 cup) if not using discard)
  • 1 tsp salt
  • 2 tsp baking soda
  • 1/2 cup sourdough discard (optional)
  • 1 cup sugar
  • 2 eggs
  • 1 stick (1/2 cup) butter
  • 1 (80z) package of cream cheese
  • 1/4 cup lime juice (fresh or bottled)
  • Zest of two limes
Bright green limes gathered together with one lime cut in half to show juicy center.


Preheat oven to 325 degrees.

Combine cake flour, salt, and baking soda. Set aside. In a separate bowl, cream together butter, cream cheese, and sugar. Add eggs and continue to cream. Once incorporated mix in lime juice (can be fresh or squeezed. I did a combination of the two).

Cake batter mixed together with cream cheese, butter, sugar, eggs, and lime juice.

Add the discard (if you have it) and dry ingredients. Mix until smooth. Incorporate the lime zest into the batter.

Cake batter mixed with dry ingredients and lime zest. Photo shows creamy white batter with bright green specks of lime zest.
Cake batter with lime zest before everything is incorporated.
Cake batter mixed right before it is poured into loaf pan for baking. Photo shows creamy batter with soft peaks.
Cake batter before poured into loaf pan and baked.

Pour the cake batter into a greased loaf pan. You can use a nonstick spray or butter. I rubbed about a little less than a tablespoon of room temperature butter on my loaf pan. Bake at 325 degrees for 75 minutes (1 hour and 15 minutes).

Let it cool in the pan for ten minutes before transferring out of pan and onto wire rack for further cooling.

Golden brown loaf cake cooling on wire rack.

After cake has cooled for at least an hour (I’d recommend longer but I couldn’t wait to try it) cut the loaf and serve with vanilla ice cream or homemade whipped cream. I went for ice cream, because it was supremely hot outside when I made this earlier this week. This could easily be eaten on its own, especially with some sort of glaze, but I think that the fresh cream taste from ice cream or whipped cream really elevates the citrus and butter notes of the dessert.

A slice of golden delicious cake with two heaping scoops of vanilla ice cream surrounding it.

If you don’t go back for seconds I recommend slicing the cake and freezing pieces for later consumption. If not, it will last in the refrigerator for 2-3 days (or however long your self-control lasts).

Elizabeth Benedict is an Associate Broker and REALTOR® at ERA Sellers and Buyers Real Estate in Albuquerque, New Mexico. She holds a Masters in Literature from the University of New Mexico. When she is not helping her community buy and sell houses she is usually writing.