sour cream biscuits

these crisp buttery biscuits are perfect with soup or stew
adapted from Food and Wine

makes about 18 
1 large egg
1 large egg yolk
3/4 cup sour cream or creme fraîche
1/4 cup milk
2 1/2 cups whole wheat flour, plus more for dusting
2 Tbsp. plus 2 tsp. sugar
1 Tbsp. plus 1/4 tsp. baking powder
2 tsp salt
1 1/2 tsp pepper
1 1/2 sticks chilled unsalted butter, cut into 1/4-inch dice
1/4 cup heavy cream
coarse salt for sprinkling

1. In a small bowl, whisk the egg with the egg yolk, sour cream and milk. In a large bowl, combine the flour with the sugar, baking powder, salt and pepper. Using a pastry blender or 2 knives, cut the butter into the flour mixture until it resembles coarse meal. Add the egg mixture and stir until the dough is evenly moistened. Gather the dough into a ball and knead 2-3 times, just until it comes together.
2. Press dough into and 8x10-inch rectangle. Cover with plastic wrap and chill for at least 30 minutes.
3. Transfer the dough to a floured surface and roll out into an 11-inch square. Fold in half and roll out again to same size. Repeat once more. Using a 2-inch round cutter (or a glass of the same size), cut out as many biscuits as possible. Gather scraps, re-roll and cut out more.
4. Preheat oven to 375º. Evenly space the biscuits on a parchment lined baking sheet. Brush tops with cream and sprinkle with salt. Bake for about 20 minutes, until golden.