01 - Whisk together the sourdough starter, lukewarm milk, eggs, melted butter, and vanilla extract in a large mixing bowl until completely smooth and emulsified.
02 - Sift together the flour, sugar, salt, baking powder, and baking soda in a separate medium bowl to ensure even distribution of leavening agents.
03 - Add the dry ingredients to the wet mixture, stirring gently with a spatula until just combined. Stop mixing as soon as flour streaks disappear to prevent tough texture.
04 - Gently fold in the diced strawberries and white chocolate chips, taking care not to crush the berries or distribute chips unevenly.
05 - Cover the bowl with a clean towel and let the batter rest at room temperature for 3–4 hours, or refrigerate overnight for enhanced flavor development through fermentation.
06 - Preheat the oven to 350°F. Generously grease a 9x5-inch loaf pan and line with parchment paper for easy removal.
07 - Give the rested batter a gentle stir to redistribute ingredients, then scrape into the prepared pan. Smooth the top with an offset spatula for even baking.
08 - Bake for 50–60 minutes until a toothpick inserted into the center emerges clean and the crown is deeply golden brown. Tent with foil if browning too quickly.
09 - Let the bread cool in the pan for 15 minutes to set structure, then carefully transfer to a wire rack to cool completely before slicing.