01 - Whisk together sourdough starter, lukewarm milk, eggs, melted butter, and vanilla extract in a large mixing bowl until fully incorporated and smooth.
02 - Sift together flour, sugar, salt, baking powder, and baking soda in a separate medium bowl to ensure even distribution.
03 - Add dry ingredients to wet ingredients, stirring gently with a spatula just until combined. Stop mixing as soon as flour disappears to prevent tough texture.
04 - Gently fold diced strawberries and white chocolate chips into batter until evenly distributed. Take care not to crush berries.
05 - Cover bowl and let rest at room temperature for 3–4 hours, or refrigerate overnight. This allows fermentation for 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 batter gently once, then transfer to prepared loaf pan. Smooth top with spatula for even baking.
08 - Bake for 50–60 minutes until top is golden brown and a toothpick inserted into center comes out clean.
09 - Let cool in pan for 15 minutes, then remove to wire rack to cool completely before slicing.