Sourdough Discard Birthday Cake Cinnamon Rolls
Fluffy, festive, and finished with glossy white 7-minute frosting — these birthday cake cinnamon rolls are the perfect from-scratch treat for any special occasion. Made with real-food ingredients and naturally-colored sprinkles.
Ingredients
For The Dough
- 3¾ cups all-purpose flour plus more for dusting
- 1 cup sourdough discard unfed
- ¾ cup whole milk room temperature
- 1 large egg
- ¼ cup honey
- ⅓ cup unsalted butter melted
- 1 tsp baking soda
- 2½ tsp baking powder
- 1 tsp fine sea salt
For The Filling
- 6 tbsp softened butter
- ¾ cup brown sugar
- 1 tbsp cinnamon optional
- ¼ tsp nutmeg
- 1 tsp vanilla extract
- 2 tbsps naturally-colored sprinkles (sprinkled over top of mixture)
7 Minute Frosting
- 2 large egg whites
- 1½ cups granulated sugar
- ⅓ cup water
- ¼ teaspoon cream of tartar
- Pinch of salt
- 1 teaspoon pure vanilla extract (mix in at the finish)
Instructions
- Make the dough: In a large bowl or the bowl of a stand mixer, whisk together flour, baking soda, baking powder, and salt. In a small bowl, whisk sourdough discard, milk, egg, honey, and melted butter. Pour wet ingredients into dry and mix on low until a shaggy dough forms. Knead on medium speed for 2–3 minutes, until smooth. Cover and let rest for 10 minutes.
- Roll and fill: On a lightly floured surface, roll dough into a 10x29” rectangle. Use a bench scraper or sharp knife to cut the rectangle in half crosswise, creating two shorter rectangles. Mis softened butter, brown sugar, cinnamon, and vanilla together. Evenly spread over surface, top with sprinkles.
- Shape and slice: Roll each rectangle tightly from the long edge into a log. Trim ends with unflavored dental floss or a sharp knife, then cut each log into about 12–13 mini rolls (roughly 1” each). I dipped each top into sprinkles before placing in baking dish to really add a some extra sparkle.
- Bake: Arrange rolls in a parchment-lined baking dish or cast iron skillet, leaving a little space between. Bake at 375°F for 20–22 minutes, until golden brown.
- Make the frosting: After rolls are done baking, combine egg whites, sugar, water, cream of tartar, and salt in a double boiler or glass bowl over pot halfway filled with water. Beat with a hand mixer on medium for about 7 minutes, until thick, glossy, and fluffy. Remove from heat and beat in vanilla.If you don't have a hand mixer (like me) whisk mixture until it reaches 140F, then pour into kitchen aid mixer and set timer for 7 minutes.
- Frost and serve: Let rolls cool until just warm to the touch before generously swirling frosting over the tops. Serve warm, topped with lots of sprinkles.
Notes
- Use naturally-colored sprinkles (plant-based dyes) for real-food results.
- Best enjoyed the same day, as the frosting is delicate.
- Make-ahead option: assemble rolls the night before, refrigerate, and bake fresh in the morning.