INGREDIENTS
3 cups
all-purpose gluten-free flour, with xanthan gum
2 1/2 tsp
baking powder
2 tbsp
sugar
1/2 tsp
salt
8 tbsp
very cold butter, cut into small pieces, plus more to grease the pan
1 1/2 cups
sour cream
2 tbsp
heavy cream, plus extra to brush the tops