Preheat oven to 400°F. Line a large baking sheet with parchment paper or a non-stick baking mat; set aside.

In a large bowl, mix together 2 1/2 cups of the flour, salt, baking powder, baking soda, and sugar.

Cut the butter into small cubes, then quickly work it into the mixture until it resembles a coarse meal.

In a small bowl, whisk together the egg and sour cream, then add to the flour and butter mixture.

In a small bowl, combine remaining tablespoon of flour, grated zucchini, and 1/2 cup of the cheese; toss to coat, then add to the scone mixture and gently fold them into the dough with a spatula until combined.

Pour the shaggy dough out onto a clean, floured work surface and shape it into an 8-inch circle. Cut the dough into 8 wedges and carefully transfer them to the prepared sheet.

Sprinkle the top of each scone with a little of the remaining cheese.

Bake for 22-24 minutes, or until cooked through and the tops are golden brown.

Serve warm!