SR flour, garlic powder, teaspoon of baking powder, butter, hard cheddar grated or cheddar/parmesan mix, yogurt.
Maybe 3 times as much flour as butter, made together into crumbs, then mix in the cheese. Mix in enough yogurt (milk is fine too but yogurt seems to do better I think) to make a dough. Roll out, and use a sharp cutter, I find if you don't they don't rise as much.
You can brush the top with an egg wash, but it only really changes the colour.
The lack of me ever bothering to measure suggests it doesn't make a whole lot of difference to the success of a recipe! I probably normally do a bit over a cup of flour and about 40g of butter, maybe 80g of cheese at a guess?
I'm not sure it's something you can particularly go wrong with.
It's not a recipe but a tip. My uncle says that scones are lighter and fluffier if you put in extra milk to make the mixture somewhat sloppy. You need to be able to dollop it out onto the baking tray with a spoon rather than roll it out and cut with a cutter. They don't look so elegant but they're much tastier.