A few notes… as with all flour-based baked goods, over-working with the flour makes them tough. Work as quickly as you can and handle the flour as little as possible.
To turn this recipe gluten-free, use Cup 4 Cup gluten-free flour blend, but reduce the flour by 1/2 cup and you’ll likely need increase the sour cream content, up to 10 Tbs! You can also make it vegan by using dairy-free yogurt in place of the sour cream and use earth balance sticks for the butter. It’s possible to freeze coconut oil and work with that as well, instead of butter – but it is MUCH more difficult to work with because the heat from your hands really melts the oil and makes the dough sticky.