01 - Whisk together sourdough starter, lukewarm milk, eggs, melted butter, and vanilla extract in a large mixing bowl until completely smooth and homogeneous.
02 - Sift together flour, sugar, salt, baking powder, and baking soda in a separate medium bowl to ensure even distribution of leavening agents.
03 - Pour dry ingredients into wet mixture, folding gently with a spatula until just combined. Stop mixing as soon as flour streaks disappear to prevent tough texture.
04 - Gently fold diced strawberries and white chocolate chips into batter, taking care not to crush fruit pieces.
05 - Cover bowl and let batter rest at room temperature for 3-4 hours, or refrigerate overnight for enhanced sourdough flavor development.
06 - Preheat oven to 350°F. Grease a 9x5-inch loaf pan thoroughly and line with parchment paper for easy removal.
07 - Stir rested batter gently to redistribute ingredients, scrape into prepared pan, and smooth surface. Bake for 50-60 minutes until deeply golden and toothpick inserted in center emerges clean.
08 - Allow bread to cool in pan for 15 minutes before transferring to wire rack. Cool fully before slicing to prevent crumbling.