Preheat your oven to 375 degrees Fahrenheit.
Start by sifting the flour, baking powder, sugar and salt into a clean, dry bowl using a sieve or sifter. Tap the sieve against the palm of your hand until all the dry ingredients have passed through it and you're left with the lumps. Push the lumps through the sieve with your finger tips.
Next, slice a vanilla bean down the centre lengthwise using a paring knife.
Open it up and scrape out as many of the teeny tiny vanilla bean seeds as you can using the back edge of your knife.
Even after you've scraped out all the vanilla seeds you can, don't throw away the rest of the bean! Pit it back in its container or in an airtight bag and reserve it for another recipe that requires you to simmer a vanilla bean (ex: homemade pudding or custard), use it in tea or even a homemade latte or steamer.
Add the vanilla bean seeds to the flour mixture and blend in using a whisk. Try your best to break up the clumps of vanilla bean seeds, but if there are a few tiny clumps left that's ok. The vanilla bean seeds will probably disappear into the flour mixture, but don't worry. They'll become visible again once the wet ingredients are added.
In a liquid measuring cup, measure the whole milk and add the egg. Whisk together using a fork and set aside.
The next few steps should be done quickly, as you're working with cold butter and you want the butter to be as cold as possible when it hits the heat of the oven. This will result in a flaky scone, rather than a heavy and dense one.
Cut up your butter, right from the fridge, into little pieces and dump it into the flour mixture.
Using your hands (wash them well first and remove any rings), pick up handfuls of the butter and flour mixture, rubbing the pieces of butter and the flour between the heels of your hands to create "sheets" of butter. You should act quickly here, and don't allow the pieces of butter to sit in your hands for any length of time as the heat from your hands will cause it to soften. The goal is to create paper-thin pieces of butter, small and large throughout the mixture. Once there are no thick chunks of butter remaining, only thin sheets, remove your hands from the mixture. Hands equal heat, so handle the mixture as little as possible.
Pour in the wet ingredients and mix roughly with a fork. Do not over mix, or the result will be heavy and dense. Once the wet ingredients have been incorporated but there are still several streaks of flour, turn the dough out onto a clean and floured counter surface. Press the dough down into the counter and then fold one half over the other half like you are folding a piece of paper. Press down again and make another fold. Repeat this 2 or 3 more times, gathering any outlying dough bits and flour into your folds. Don't knead the dough like you would if you were making bread, and don't stir or mix the dough like you would if you were making muffins. Scones are technically a pastry, so the goal is flaky layers that are created by the thin sheets of butter and all the folding.
Once your dough is formed after folding several times, shape it into a 10-inch circle (approximately).
Again, be careful not to handle the dough too much, so a few little cracks here and there are fine.
Cut the circle into eight triangles with a very sharp knife (like you'd slice a pizza)
Arrange the 8 triangles on a parchment-lined baking sheet and bake for about 18-22 minutes. I usually set the timer and start watching them after about 16 minutes. You want them to stay nice and white and not get too brown, especially on the narrow end of the triangle.
Remove them from the oven when they're just barely golden brown on the bottom and the surface of the scones lose their shine. Let them cool for 3-5 minutes on the baking sheet. Transfer them to a cooling rack to cool completely.