Preheat your oven at 400°F (204°C). Line a large baking sheet with parchment paper.
In your stand mixer bowl, sift your flour, baking powder, sugar, salt, matcha powder and mix together.
With a paddle attachment, add the cubed cold butter and mix at level Stir or 2 till mixture looks like coarse meal. This takes about 3-4 minutes. You need to watch closely so it does not become a paste.
If you do not have a stand mixer, you can use a pastry cutter, two forks or your fingers to mix the butter with the flour till it comes together like crumbs.
In a separate bowl, whisk together your heavy cream/butter milk, egg and vanilla extract together. Drizzle your milk mixture to your flour mixture and mix until just combined. There may still be some loose crumbs.
Pour your dough to a floured counter. Work the dough into a ball as best as you can. Depending on what Add-Ins you have, the dough can be on the wet/sticky side. If so, add a little more flour till the dough is coming together. If the dough seems too dry, add 1-2 Tablespoons of Heavy Cream.
Press dough to an 8 Inch Round disk and about ½ inch thick. With a bench scraper or knife, cut into 8 wedges. At this point, place the scones in the refrigerator for about 15 minutes. Or you can place the scones on a lined baking sheet and put it in the refrigerator. Make sure the scones are about 2-3 inches apart, it will spread a bit in the oven.
After taking out your scones from your refrigerator, brush the scones with heavy cream/buttermilk.
Bake for about 22-25 minutes till top and edges are golden brown.