Steak with Fondant Potatoes and Pickled Shallots

Introduction

This is my favorite kind of steak dinner: few components, each treated with care. Fondant potatoes are essentially pan-browned potato cylinders that absorb stock as they roast, becoming buttery and deeply savory. Pickled shallots add the acidity that keeps the plate lively.

And yes, use a thermometer. For a steak you care about, it is the simplest insurance against overcooking.

Quick overview: Trim the potatoes so they can stand upright, brown them well in butter and oil, add stock halfway up the sides, and finish in the oven until tender. Quick-pickle shallots for a bright acidic contrast. Sear the steak hard on both sides, then finish in 5-minute oven intervals if needed until it reaches your target internal temperature. For premium cuts, I like 48 °C / 118 °F before resting. Serve with pepper sauce and shiitake cooked in the same pan.

Step-by-step

Ingredients (serves 2)

Fondant potatoes

• 800 g potatoes (1.75 lb), peeled
• 30 g butter (2 tbsp)
• 20 ml neutral oil (1½ tbsp)
• 4 dl stock (about 1 2/3 cups) (chicken or beef)
• Salt and black pepper

Quick pickled shallots

• 4 shallots, thinly sliced into rings
• 1 dl vinegar (about 1/2 cup)
• 1 dl water (about 1/2 cup)
• 40 g sugar (about 3 tbsp)
• 6 g salt (about 1 tsp)

Steak and mushrooms

• 2 steaks, about 180–220 g each (6–8 oz)
• 150 g shiitake mushrooms (5 oz), torn or chopped
• 20 ml oil (1½ tbsp)
• 20 g butter (1½ tbsp)
• Salt and black pepper

Pepper sauce (simple)

• 1–2 tbsp black peppercorns, coarsely crushed
• 2 dl stock (about 3/4 cup + 2 tbsp)
• 3 dl heavy cream (about 1 1/4 cups)
• Salt

Method

1. Preheat the oven to 200 °C / 390 °F.
2. Pickled shallots: Bring vinegar, water, sugar, and salt to a boil. Pour over the sliced shallots and let sit at least 20 minutes.
3. Fondant potatoes: Trim the ends so each potato can stand upright. If they’re large, cut into “barrels.”
4. Heat an oven-safe skillet over medium-high. Add butter and oil and brown the potatoes well on both flat sides.
5. Pour in stock until it comes about halfway up the potatoes. Season lightly with salt and pepper.
6. Transfer the pan to the oven and roast until tender, usually 35–55 minutes depending on size. Spoon some of the stock over the tops once or twice while they cook.
7. Pepper sauce: Crush the peppercorns. Simmer stock with pepper for 3–5 minutes. Add cream and reduce to your preferred thickness. Season with salt.
8. Steak and mushrooms: Pat the steaks dry and season well with salt and pepper. Sear hard in a very hot pan with oil, about 2–3 minutes per side for a solid crust. Add butter and baste.
9. Cook the mushrooms in the same pan for 1–2 minutes while the steak gets a bit more color. If the potatoes are still in the oven, move the steak in for 5-minute intervals until you hit your target internal temp.
10. Rest the steak 5–10 minutes. For a great cut, I like 48 °C / 118 °F before resting.
11. Serve: Plate the potatoes, spoon over a little of the concentrated potato stock, then add steak, mushrooms, pepper sauce, and a small pile of pickled shallots.

Tips

• Bigger potatoes work better here. Small pieces quickly turn into “just roasted potatoes.”
• Leftover pickling liquid is great in salad dressings.