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This Entrecôte Wagyu Burger with Frites is the juiciest, most flavorful burger you will ever bite into, and the whole thing is built around a sauce that a French family has refused to hand over since 1959.
In Paris there is a small group of restaurants called L’Entrecôte. There is no menu to read. You sit down, they bring you a green salad with walnuts, then steak frites in a green herb butter sauce, and then they come back and give you a second helping of both without asking. That is the entire business, and people love it.
This is my version of it, on a burger. Two wagyu patties with gruyere melted over them and pickled jalapeños in between, on toasted brioche spread with honey mustard mayonnaise. Caramelized onions go on next, then a wagyu strip steak off the same griddle, chopped. I cut the whole thing in half and stand it up in a pool of the sauce, and the matchstick frites go in after it.
Table of Contents
The Wagyu Beef
Wagyu is known for its buttery texture and amazing flavor. That’s because it’s the most marbled beef you can buy. The Japanese have been breeding cattle for that marbling for generations. The fat is softer than regular beef fat, so it melts while the burger is still cooking and the patty bastes itself from the inside. That is where the tenderness comes from.
I like to use the griddle for these because it keeps them nice and juicy instead of the fat just dripping through the grates. The patty develops a deep brown crust while the inside stays buttery tender with all that flavor.
I also use a wagyu New York strip. It goes on the griddle with the patties. This is the cut the entrecôte sauce was made for. The restaurants in Paris serve contre-filet, which is the same steak under a French name.
Keep the uncooked patties cold until they go on the griddle. You will see a lot of advice about letting meat come up to room temperature before it cooks. Not with these. Wagyu fat has a low melting point, so the patties go on straight out of the fridge.
No wagyu? Use 80/20 ground chuck for the patties and a regular New York strip for the steak. Go by internal temperature instead of the clock, since leaner beef dries out faster past medium rare.
The Secret Ingredient
This secret ingredient makes your wagyu patties taste like they have been roasting all afternoon. And that is exactly what it is. Better Than Bouillon Roasted Beef Base is real roasted beef and concentrated beef stock cooked down into a savory paste. I add it in place of salt and it adds so much depth to the flavors.
The Entrecôte Sauce
This is the sauce people wait in line on a sidewalk for. This sauce is buttery, full of fresh herbs, savory, slightly tangy, peppery, literally everything you could want in a steak sauce. Which makes sense because it was developed specifically for a nice cut of steak.
My version is definitely simplified from the original, but trust me, you will want to dip everything on your plate in it still and you’ll make it in much less time.
How to Serve
I like to cut the burger in half and stand the halves up in a pool of sauce. The bun soaks from the bottom up so the sauce gets into the layers instead of sitting on the outside. The frites go in next to it, right into the sauce, and there is a ramekin of extra sauce on the side because you will run out.
For the rest of the menu: a Blue Cheese Dirty Martini before anyone sits down, Crispy Fried Zucchini and Eggplant while the frying oil is already hot, Arugula Fennel Salad on the side because the lemon and raw fennel are the only things here that are not butter or fried, and S’mores Ice Cream Cake for dessert since it comes out of the freezer and nobody is baking after all this.
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Frequently Asked Questions
It is the green sauce that they over steak frites at the L’Entrecôte restaurants in Paris. The recipe has never been released. Every version you find online, including mine, is somebody’s reconstruction.
Yes. Use 80/20 ground chuck for the patties and a regular New York strip for the steak. Cook to temperature rather than time, since leaner beef dries out faster past medium rare.
No, but you want a flat surface. Cast iron works. The reason not to use a grill is that wagyu renders a lot of fat and on a grate all of it drops into the fire instead of frying the patty.
I wouldn’t. The green is brightest right after you blend it and fades as it sits, faster each time it goes back on the heat, so it looks best made the day you serve it.
Equipment
- large bowl
- Small heavy saucepan
- Deep-fry thermometer
- spider strainer
- Wire rack set over a rimmed baking sheet
- large skillet
- Bullet or immersion blender
- parchment paper
- griddle
Ingredients
Frites
- 3 large russet potatoes, about 2 lbs, peeled
- neutral oil, for frying
- 2 tbsp chives, finely chopped
- kosher salt
Caramelized Onions
- 1 tbsp olive oil
- 1 tbsp unsalted butter
- 2 large yellow onions, halved and thinly sliced
- 1/4 tsp kosher salt
Entrecote Sauce
- 4 tbsp unsalted butter
- 1 tbsp olive oil
- 1 large shallot, minced
- 2 anchovy fillets
- 1 tbsp crushed pistachios
- 1 1/2 tbsp capers, drained
- 1 tbsp brined green peppercorns, drained
- 1 1/4 tsp Better Than Bouillon roasted beef base
- 2 oz cognac
- 2 tsp white wine vinegar
- 1 1/4 cups beef stock
- 1/4 cup fresh chives, rough chop
- 10 basil leaves
- 1/4 cup fresh flat leaf parsley leaves, packed
- 2 tbsp fresh tarragon leaves, packed
Spread
- 1/2 cup mayonnaise
- 1 tbsp dijon mustard
- 1 tbsp balsamic vinegar
- 1 tbsp honey
- 1 tsp Better Than Bouillon roasted beef base
Burgers
- 2 lbs ground wagyu beef
- 2 tbsp Better Than Bouillon roasted beef base
- 1 1/2 tsp smoked paprika
- 1 1/2 tsp garlic powder
- 3/4 tsp ground white pepper
- 1 wagyu new york strip steak, about 12 oz
- kosher salt and freshly ground black pepper, for the steak
- 8 oz gruyere, sliced
- 4 brioche buns, split
- 2 tbsp unsalted butter, softened
- 1/2 cup pickled jalapeño slices, drained
Instructions
- Soak the Potatoes: Run the potatoes through a mandoline into 1/8 inch planks. Stack the planks and cut them lengthwise into 1/16 inch matchsticks. Transfer to a large bowl, cover with ice water by 2 inches, and refrigerate 2 to 24 hours.3 large russet potatoes
- Caramelize the Onions: Preheat a skillet over medium-low heat for 2 minutes. Add the olive oil and onions. Cook 25-30 minutes, stirring every few minutes. Add in the butter and salt, cook another 20-30 min adding a tablespoon of water whenever the pan looks dry and there’s stuck on bits to deglaze, until deep golden. Transfer to a bowl and keep warm.1 tbsp olive oil, 1 tbsp unsalted butter, 2 large yellow onions, 1/4 tsp kosher salt
- Make the Sauce: Add the butter and olive oil to a small saucepan over medium-low heat. Once the butter has melted, add the shallot and cook 4 minutes, until translucent. Add the anchovies, crushed pistachios, capers, green peppercorns, Better Than Bouillon, and cognac. Cook 2-3 minutes. Add the vinegar and the stock and simmer for 5-7 more minutes. Add the chives, basil, parsley, and tarragon. Transfer to a blender and blend until completely smooth and uniformly green. Return to the pan and simmer over low heat until thickened.4 tbsp unsalted butter, 1 tbsp olive oil, 1 large shallot, 2 anchovy fillets, 1 tbsp crushed pistachios, 1 1/2 tbsp capers, 1 tbsp brined green peppercorns, 1 1/4 tsp Better Than Bouillon roasted beef base, 2 oz cognac, 2 tsp white wine vinegar, 1 1/4 cups beef stock, 1/4 cup fresh chives, 10 basil leaves, 1/4 cup fresh flat leaf parsley leaves, 2 tbsp fresh tarragon leaves
- Blanch the Frites: Drain the potatoes and pat them completely dry with paper towels, pressing out every bit of surface water. Fill a small heavy saucepan with 1 to 1 1/2 inches of oil and heat to 325°F (163°C). Fry in small batches 2 to 3 minutes, until limp and pale with no color. Remove with a spider strainer to a wire rack. Freeze at least 30 minutes.neutral oil
- Make the Spread: Whisk the mayonnaise, dijon, balsamic, honey, and Better Than Bouillon in a small bowl until smooth.1/2 cup mayonnaise, 1 tbsp dijon mustard, 1 tbsp balsamic vinegar, 1 tbsp honey, 1 tsp Better Than Bouillon roasted beef base
- Form the Patties: Break the wagyu into loose chunks in a large bowl. Add the Better Than Bouillon, smoked paprika, garlic powder, and white pepper. Fold gently until just combined. Divide into 8 portions and roll each into a ball. Set a ball on a parchment-lined plate, cover with a second sheet of parchment, and press flat with another plate into a patty slightly wider than the buns. Repeat with the rest. Refrigerate until they go on the griddle.2 lbs ground wagyu beef, 2 tbsp Better Than Bouillon roasted beef base, 1 1/2 tsp smoked paprika, 1 1/2 tsp garlic powder, 3/4 tsp ground white pepper
- Cook the Steak and Patties: Season the strip steak with salt and pepper. Heat the griddle to medium-high, 400 to 425°F (200 to 220°C). Cook the steak and the patties together, the steak 4 to 5 minutes per side and the patties 2 to 3 minutes per side, flipping each once, to an internal temperature of 130 to 135°F (54 to 57°C). That is where I like them. See the notes for every other doneness temperature. Lay the gruyere over each patty during the last minute and cover to melt. Transfer the steak to a cutting board and rest 10 minutes.1 wagyu new york strip steak, kosher salt and freshly ground black pepper, 8 oz gruyere
- Toast the Buns: Butter the cut sides of the buns. Toast cut side down on the griddle 1 to 2 minutes, until golden.4 brioche buns, 2 tbsp unsalted butter
- Fry the Frites: Heat the fry oil to 375°F (190°C). Fry the frozen potatoes in small batches 1 to 2 minutes, until golden and crisp. Remove with a spider strainer to a wire rack. Toss with the parsley and salt to taste.2 tbsp chives, kosher salt
- Assemble: Slice the rested steak and roughly chop. Spread the bun bottoms with the honey mustard mayonnaise. Add a patty, then the pickled jalapeños, then a second patty. Pile on the caramelized onions and the chopped steak. Close the buns and cut each burger in half. Pool the warm sauce on the plates and stand the halves in the sauce. Serve with the frites and a ramekin of extra sauce.1/2 cup pickled jalapeño slices
Kitchen Cam
Notes
Rare: 120 to 125°F (49 to 52°C)
Medium rare: 130 to 135°F (54 to 57°C)
Medium: 140 to 145°F (60 to 63°C)
Medium well: 150 to 155°F (66 to 68°C)
Well done: 160°F (71°C) These are the same whether or not you’re using wagyu.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
