1/2 tsp salt fine sea or table
13 tbsp unsalted butter cold, diced
6 tbsp sour cream or Greek-style yogurt
1 whole egg beaten with 1 tsp water, for egg wash
black pepper freshly ground
3.5 to 4 lbs chicken parts bone-in, skin-on; breasts, thighs, and drumsticks are ideal
2 medium leeks white and light green parts only, cut in half lengthwise and then into 1/2-inch slices
1 large onion diced small
1/4 cup dry sherry optional
3 cups chicken broth low-sodium
1/4 cup milk or heavy cream
1 tsp thyme minced, fresh
3 tbsp unsalted butter at room temperature
4.5 tbsp all-purpose flour
1 cup green peas fresh or frozen; no need to defrost
2 large carrots diced small (about 1 cup)
2 tbsp parsley chopped flat-leaf