Pan-Seared Steak Diane with Herb Roast Potatoes
Steak Diane is a classic French-British bistro dish featuring tender beef in a rich, tangy pan sauce of brandy, stock, and horseradish cream. This version pairs it with crispy roast potatoes infused with garlic and fresh herbs. What makes it special is the balance of umami-forward flavors: peppery beef, sharp horseradish bite, and brandy's warmth, all mellowed by silky crème fraîche. The sauce clings to sliced steak, creating restaurant-quality depth at home. Key textures range from the steak's crust to creamy sauce and golden potatoes. Perfect for dinner guests or a special weeknight meal, it showcases British dry-aged beef and enhances simple ingredients through technique. Roasting potatoes alongside means minimal pan management while the sauce comes together quickly in the same pan used for searing, building fond-based flavor that defines the dish.
Ingredients
- 11 oz waxy potatoes such as charlotte, cut into wedges
- olive oil, for drizzling
- 4 cloves garlic, unpeeled and bashed
- 2 sprigs fresh rosemary, whole
- 2 sprigs fresh thyme, whole
- 2 x 200 g, British dry-aged sirloin or rump steaks
- ¼ tsp black peppercorns, crushed in a pestle and mortar
- ½ tsp green peppercorns, crushed in a pestle and mortar
- watercress, to serve
- olive oil, splash
- 2 whole shallots, finely sliced
- 2 tbsp brandy
- 10 tbsp beef or chicken stock
- 3 tbsp crème fraîchesour cream1:1dairytangyadds dairy
slightly more acidic, less rich. Adds:none
- 1 tbsp hot horseradish cream from a jarwasabi0.5:1spicypungentdairy-free
less traditional, sharper heat. Removes:none Adds:none
Instructions
- 1
Heat oven to 400°F.
- 2
Toss potatoes with oil, unpeeled bashed garlic cloves, rosemary, thyme, salt, and pepper in a roasting tray. Roast for 25 minutes, shaking halfway through, until tender and golden.
- 3
After potatoes have roasted for 15 minutes, heat oil in a large heavy-based frying pan over medium-high heat.
- 4
Season steaks with salt and most of both crushed peppercorns. Cook in the pan for 3 minutes per side for medium-rare. Remove and rest.
- 5
Heat a splash of oil in the same pan over medium heat. Add finely sliced shallots and cook, stirring, for 4-5 minutes until golden.
- 6
Add brandy and bubble on high heat until most has evaporated.
- 7
Add stock and return to the boil, scraping up browned bits from the pan base with a wooden spoon.
- 8
Turn heat to low. Stir in crème fraîche and horseradish cream, then season.
- 9
Slice the rested steak and return to the pan with sauce.
- 10
Serve with herby roast potatoes, sauce, and watercress.
Tips
Score or rest steak well before cooking. Temperature carryover (3-5°C rise during resting) is crucial for medium-rare consistency. Remove from pan 2-3°C below target internal temperature.
Fond is everything in Diane sauce. After removing steak, deglaze the hot pan with brandy immediately to dissolve caramelized beef bits, then add stock. Don't skip the wooden spoon scraping.
Use waxy potatoes like Charlotte that hold shape when roasted. Floury varieties collapse. Cut to uniform wedge size so they cook evenly without drying out at the edges.
Good to Know
Leftover sliced steak keeps in an airtight container up to 3 days. Store separately from potatoes to prevent sogginess. Reheat sauce gently over low heat with a splash of stock.
Prepare potatoes and ingredients up to 4 hours ahead. Do not roast or sear until ready to serve; Diane is best served immediately after plating.
Plate steak slices on warmed plates. Spoon sauce over top. Arrange roast potatoes and fresh watercress alongside. Serve immediately with crusty bread to soak sauce.
Common Mistakes
Don't skip resting the steak to avoid loss of juices when slicing, resulting in dry meat and a wetter plate.
Don't crowded the pan when searing steaks to avoid steaming instead of browning, which prevents crust development.
Don't add crème fraîche to boiling sauce to avoid curdling; reduce heat to low first.
Substitutions
Dairy-Free Swaps
less traditional, sharper heat. Removes:none Adds:none
General Alternatives
equally suitable per recipe. Removes:none Adds:none
fattier, more indulgent. Removes:none Adds:none
FAQ
Can I make the sauce ahead of time?
Partially. Prepare shallots and measure ingredients, but do not make the full sauce until just before serving. The brandy reduction and final assembly work best fresh to preserve the bright, hot horseradish bite and avoid separation of fats.
What if I don't have horseradish cream?
Fresh grated horseradish mixed with a dollop of sour cream works well, though adjust quantity to taste. Dijon mustard is a milder alternative. Avoid omitting entirely, as horseradish defines the Diane flavor profile.
Can I freeze leftover steak and sauce?
Yes, up to 1 month. Cool completely, transfer to freezer containers, and thaw overnight in the refrigerator. Reheat sauce gently over low heat, stirring often. Potatoes do not freeze well due to texture loss; enjoy fresh only.