In a bowl or straight edge container, mix together the lemonade, lemon zest, active starter, and salt until the starter is dissolved with a dough whisk. Add the bread flour and mix until a shaggy dough is formed. Let sit in a warm spot covered for about 30 minutes.400 grams lemonade, zest of 1 lemon, 150 grams active sourdough starter, 10 grams salt, 500 grams bread flour

Perform 2-3 sets of stretch and folds to develop the gluten in the dough with at least a 30 minute rest in between each set. Add the blueberries during the first set of stretch and folds. To stretch and fold the dough, grab one side with a damp hand and gently shimmy the dough up, and then fold it on itself. Repeat this 3 more times rotating the bowl 90 degrees each time.280 grams blueberries

Continue to let the dough rise for bulk fermentation until it is risen 50% and is jiggly with bubbles forming around the sides of the bowl. With dough in the mid 70’s F, the first rise will take about 5 hours from the time it is mixed.

Add 2 Tablespoons of melted butter in a greased 9×13 pan and add the focaccia dough. Spread out the dough and coat both sides with butter.

Let it rise another hour or two covered in a warm spot until it has risen well and is puffy.

Melt the remaining 2 Tablespoons of butter and add on top of the dough. Dimple the dough with your fingers and bake in the oven at 425°F degrees for 27-30 minutes.

While the focaccia is baking, whisk together powdered sugar and lemonade to make the glaze. If your glaze is too thick, add another Tablespoon of lemonade. 120 grams powdered sugar, 30 grams lemonade

After the focaccia has finished baking, add it to a cooling rack and let it cool. Drizzle the lemon glaze on top of the baked focaccia while it is still warm and serve.