For the glaze whisk powdered sugar, lemon juice and zest together. Add butter and heat in the microwave for 45 seconds. Whisk until smooth. Let sit for a few minutes and drizzle over bread.
Zest of one lemon, ¼ cup (60 grams, about 1 whole lemon) lemon juice, 1 cup + 2 tablespoons (270 grams) warm water, ½ cup (100 grams) active sourdough starter, 4 cups + 2 tablespoons (500 grams ...