01 - Whisk together the sourdough starter, lukewarm milk, eggs, melted butter, and vanilla extract in a large mixing bowl until smooth and fully incorporated.
02 - In a separate medium bowl, sift together the flour, sugar, salt, baking powder, and baking soda until evenly distributed.
03 - Add the dry ingredients to the wet ingredients, stirring gently with a spatula until just combined. Take care not to overmix as this can result in a dense texture.
04 - Gently fold in the diced strawberries and white chocolate chips until evenly distributed throughout the batter.
05 - Cover the bowl and let the batter rest at room temperature for 3–4 hours, or overnight in the refrigerator, to allow proper fermentation and flavor development.
06 - Preheat the oven to 350°F. Grease a 9x5-inch loaf pan and line with parchment paper for easy removal.
07 - Give the rested batter a gentle stir to recombine, then scrape it into the prepared loaf pan. Smooth the top with a spatula for even baking.
08 - Bake for 50–60 minutes, or until a toothpick inserted into the center comes out clean and the top is deep golden brown.
09 - Allow to cool in the pan for 15 minutes, then carefully transfer to a wire rack to cool completely before slicing.