Add baking soda, flour, salt, and baking powder to the bowl of a mixer or food processor. Hit the pulse button a few times to disperse the ingredients.
2 cups all-purpose flour, 1 teaspoon baking powder, ¼ teaspoon baking soda, ½ teaspoon salt
Add the egg and sour cream and pulse to combine thoroughly.
½ cup sour cream, 1 large egg
Next, add in the cubed butter and pulse until the mixture comes together - it will be a little crumbly but should stick together.
8 tablespoons butter
Now add the ham, cheese, and green onions. Pulse just a few times - you don't want to overmix, but you want to evenly disperse all the ingredients.
1 cup shredded/grated cheese, 1 cup diced cooked ham, ¼ - ½ cup green onions
Now, turn the dough out onto a clean piece of parchment paper and press all the crumbles together to form a large circle - like a frisbee made of dough - about 7 or 8 inches across and about ¾-inch thick. Wrap the circle of dough with the parchment paper and place it in the freezer for about 10 minutes.
This will make 8 scones. To make bite-sized scones, make two smaller circles that are a little thinner.
While the dough chills in the freezer, preheat your oven to 400°F. It should heat up in the same amount of time that it takes for the dough to chill just the right amount.
Now, remove the dough and cut it up like a pizza. In half, then into quarters, then into eighths. This should produce 8 equal-sized scones.
Separate the scones and form the edges just a little bit - you don't want to handle the dough too much - then place them on a lined baking sheet.
Bake at 400°F until golden - this should take 10 - 15 minutes.
Eat the scones immediately while they are nice and warm from the oven.