Cod Braised with Leeks, Potatoes, and Thyme

Ingredients

• 1 ½ cups bottled clam juice or chicken stock
• 2 teaspoons Dijon mustard
• 2 tablespoons capers, drained
• 3 thyme sprigs
• ½ cup dry white wine, Sauvignon Blanc
• 1 pound Yukon Gold potatoes, peeled, thinly sliced
• 2 leeks, white and 1-inch of the green, thinly sliced
• Salt and freshly ground black pepper
• 1 ½ pound cod fillets, cut into 6 serving pieces
• 1 teaspoon lemon juice
• 1 teaspoon freshly grated lemon zest