01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - Whisk together all-purpose flour, baking powder, baking soda, and fine sea salt in a large bowl.
03 - Whisk together whole milk, sour cream or Greek yogurt, egg, and truffle oil until smooth in a separate bowl.
04 - Add the wet mixture to the dry ingredients and fold gently just until combined. Avoid overmixing.
05 - Fold in fresh chives or parsley and Parmesan cheese if desired.
06 - Drop 8 mounds of dough onto the prepared baking sheet using two spoons or an ice cream scoop, spacing them 2 inches apart.
07 - Bake for 10 to 12 minutes, until scones are golden brown and puffed.
08 - Remove from oven and immediately brush tops with extra truffle oil. Serve warm.