Cod & Potatoes in a Rosemary Cream Sauce

3 T olive oil
1 lb Yukon gold potatoes, cut into 1-inch pieces
2 t kosher salt
¼ t freshly cracked black pepper
2 T salted butter
1 small onion, chopped
3 cloves garlic, minced
1 cup heavy cream
½ cup chicken stock
2 sprigs fresh rosemary
1 t lemon zest
2 T lemon juice
2 t Dijon mustard
¼ t ground cayenne pepper
2 T capers, drained
1 pound cod fillet, cut into 4 pieces

Preheat the oven 450°F with a rack in the center position. Grease an 8x8-inch baking dish with olive oil.

Add the potatoes and toss with 1 T oil, 1 t salt, and the black pepper. Roast until tender, 20-25 minutes.

Meanwhile, heat the butter and remaining 1 T oil in a medium saucepan over medium heat. Once the butter has melted add the onion and cook, stirring, until tender, about 5 minutes. Add the garlic and cook until fragrant, about 1 minute more.

Add the cream, stock, rosemary sprigs, lemon zest, lemon juice, mustard, cayenne, and capers. Increase the heat to medium-high and bring to a simmer. Reduce the heat to medium low and cook until it begins to thicken, about 5 minutes.

Sprinkle the cod all over with the remaining 1 teaspoon salt.

Remove the potatoes from the oven, nestle in the fish and pour the sauce over the top. Bake uncovered until the fish is flakey, another 10-15 minutes.

(insert smiley face here)