Instructions
Preheat and Prepare Baking Sheets
Heat your oven to 425°F (218°C). Line two large baking sheets with parchment paper or silicone baking mats and set them aside.
Prepare the Zucchini
Place the shredded zucchini in a colander or a bowl lined with paper towels, a kitchen towel, or cheesecloth. Sprinkle with 1/2 teaspoon of salt and gently toss. Let it rest for 10 minutes. Press down with another towel to absorb moisture, then wring and squeeze out as much liquid as possible. You should have about 1/2 cup of zucchini left.
Combine Dry Ingredients
In a large bowl or food processor, mix the flour, remaining 1/2 teaspoon of salt, baking powder, baking soda, garlic powder, black pepper, and Parmesan cheese. Whisk or pulse until combined.
Incorporate Butter
Add the cold, cubed butter to the dry ingredients. Use a pastry cutter, two forks, or the food processor to cut the butter into the mixture until it resembles coarse crumbs. Avoid over-mixing. If using a food processor, transfer the mixture to a large bowl.
Integrate Zucchini and Herbs
Stir in the prepared zucchini, basil, and parsley. Create a well in the center of the mixture and pour in 1 cup of cold buttermilk. Fold gently with a spatula until a shaggy dough forms. Add a little flour if the dough feels too wet, but avoid overworking it.
Shape the Biscuits
Divide the dough into 12 equal portions, about 4 tablespoons or 65 grams each. Shape them into balls and place six on each prepared baking sheet. Brush the tops with the remaining buttermilk and, if desired, sprinkle with flaky sea salt.
Bake
Bake for 19–21 minutes, or until the tops are golden brown and an instant-read thermometer inserted in the center registers 195–200°F (90–93°C).
Serve and Store
Enjoy the biscuits warm. Store leftovers in an airtight container at room temperature or refrigerate for up to five days.