Ingredients
Dough
- 100 g active sourdough starter (fed and bubbly)
- 350 g bread flour
- 100 g all-purpose flour
- 220 g whole milk, lukewarm
- 50 g granulated sugar
- 1 large egg
- 50 g unsalted butter, softened
- 8 g salt
- 1 tsp vanilla extract
Mix-ins
- 80–100 g rainbow jimmies sprinkles (avoid nonpareils, which can bleed color)
Optional Glaze
- 1 cup powdered sugar
- 2–3 tbsp milk
- ½ tsp vanilla extract
- Extra sprinkles for topping
Instructions
1. Mix the Dough
- In a large bowl, combine starter, milk, egg, sugar, and vanilla.
- Add both flours and mix until no dry flour remains.
- Rest for 30 minutes.
- Add salt and softened butter.
- Knead until smooth and elastic (8–10 minutes by hand or 5–6 minutes in a mixer).
2. Bulk Fermentation
- Cover and let rise at room temperature for 4–6 hours.
- Perform 3 sets of stretch-and-folds during the first 90 minutes.
3. Add the Sprinkles
- During the final fold, gently incorporate the rainbow sprinkles.
- Fold carefully to avoid crushing them.
4. Shape
- Shape into a tight loaf or boule.
- Place in a greased loaf pan or proofing basket.
5. Cold Proof
- Cover and refrigerate 8–12 hours overnight.
- This develops flavor and makes scoring easier.
6. Bake
- Preheat oven to 375°F (190°C).
- If using a Dutch oven, preheat it as well.
- Bake:
- 25 minutes covered
- 20–25 minutes uncovered
- Internal temperature should reach about 200°F (93°C).
7. Cool
Allow the bread to cool completely before slicing.
Optional Vanilla Glaze
- Whisk powdered sugar, milk, and vanilla until smooth.
- Drizzle over cooled bread.
- Sprinkle extra rainbow sprinkles on top.
Tips for Success
Use Active Starter
Your starter should be at peak activity and able to double in size within 4–6 hours after feeding.
Choose the Right Sprinkles
- Use jimmies (long soft sprinkles).
- Avoid tiny nonpareils because they can melt and discolor the dough.
Don’t Overmix the Sprinkles
Gentle folding preserves the colorful appearance.
For Extra Cake Flavor
Add:
- ¼ tsp almond extract
- 1 tbsp dry milk powder
For Softer Bread
Replace 20 g of the milk with heavy cream.
Storage
- Store at room temperature for up to 3 days.
- Freeze slices for up to 2 months.


