There’s something truly special about a good sandwich. It’s more than just bread and fillings; it’s about the flavors, the textures, and the experience of biting into something delicious. Now, imagine combining the rich, savory taste of a perfectly smoked steak with the deep, caramelized flavors of French onions. Add to that a zesty horseradish sauce that packs just the right amount of kick, and you’ve got yourself a sandwich that’s out of this world.

This isn’t just any sandwich; it’s the French Onion Steak Sandwich. Whether you’re a seasoned chef or someone who just loves a good meal, this recipe is for you. It might sound fancy, but don’t let that intimidate you. We’ve broken it down into simple steps, so you can make this mouthwatering sandwich right in your kitchen. Ready to dive in? Let’s get cooking!

Ultimate Creamy Horseradish Sauce Recipe

Start by preparing the Creamy Horseradish Sauce. In a mixing bowl, combine 1/2 cup each of mayo and sour cream, 1 tablespoon of Horseradish sauce, 1 tablespoon of Dijon mustard, the juice of 1 lemon, zest from 1/2 a lemon, 2 teaspoons each of chopped rosemary and chives, and 1 teaspoon of black pepper. Mix everything well and refrigerate until you’re ready to use it.

Authentic French Onion Preparation Guide

For the French Onions, heat a skillet over medium heat and melt 2 tablespoons of beef tallow. Add 2 diced large white onions and sauté for about 15 minutes. Season with 2 teaspoons of kosher salt, then stir in 6 minced garlic cloves, cooking for another 30 minutes. Pour in 1 cup of beef broth and 3 tablespoons of dark lager beer, allowing the mixture to simmer until reduced, which should take about 20-30 minutes. Finish by stirring in 1 tablespoon of chopped rosemary and 1 tablespoon of chopped parsley, cooking for an additional 10 minutes. Once done, set aside and keep warm.

How To Smoke A Steak

Before you begin with the onions, prepare your steaks. Rub them with olive oil and binder, then season generously with Steak King seasoning. Allow the steaks to sit at room temperature while you work on the onions. Once the onions are ready, smoke the steaks on a smoker preheated to 250°F, using hickory wood chunks for flavor. The steaks should be smoked until they reach an internal temperature of 118°F. Afterward, give them a quick sear for 60-90 seconds on each side. Let the steaks rest for 8-10 minutes after removing them from the heat.

Assembling the Best French Onion Steak Sandwich

While the steaks are resting, toast some French Sub Buns. When ready to assemble your sandwich, spread a generous amount of the horseradish sauce on the bottom bun, layer with three slices of Swiss cheese, add your thinly sliced steak, another three slices of Swiss cheese, and top with the warm French onions. Cap it off with the top bun. Place the assembled sandwich in an oven preheated to 425°F and bake for 8-10 minutes.

Serving Suggestion

Serve your delicious French Onion Steak Sandwich hot and enjoy!

Ingredients:

Creamy Horseradish Sauce:

1/2 cup mayo
1/2 cup sour cream
1 tablespoon Horseradish sauce
1 tablespoon Dijon mustard
1 lemon, juiced
1/2 lemon, zest
2 teaspoons rosemary, chopped
2 teaspoons chives, chopped
1 teaspoon black pepper

French Onions:

2 large white onions, diced
6 cloves garlic, minced
1 cup beef broth
3 tablespoons dark lager beer
1 tablespoon rosemary, chopped
2 teaspoons kosher salt
2 tablespoons beef tallow
1 tablespoon parsley, chopped

For the Steak:

3 Ribeye Steaks
Olive oil
Binder
Steak King seasoning

Additional Ingredients:

French Sub Buns
Swiss cheese slices
Hickory wood chunks (for smoking)

Below is a printable recipe card!

French Onion Steak Sandwich

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Ingredients

Creamy Horseradish Sauce:

1/2 cup mayo
1/2 cup sour cream
1 tablespoon Horseradish sauce
1 tablespoon Dijon mustard
1 lemon juiced
1/2 lemon zest
2 teaspoons rosemary chopped
2 teaspoons chives chopped
1 teaspoon black pepper

French Onions:

2 large white onions diced
6 cloves garlic minced
1 cup beef broth
3 tablespoons dark lager beer
1 tablespoon rosemary chopped
2 teaspoons kosher salt
2 tablespoons beef tallow
1 tablespoon parsley chopped

For the Steak:

Olive oil
Binder
Steak King seasoning
Additional Ingredients:
French Sub Buns
Swiss cheese slices
Hickory wood chunks for smoking

Instructions

In a bowl, combine mayo, sour cream, horseradish, Dijon mustard, lemon juice, zest, rosemary, chives, and pepper. Mix well and refrigerate.
Heat beef tallow in a skillet. Add onions and sauté for 15 minutes. Stir in garlic and salt, cooking for an additional 30 minutes. Pour in beef broth and beer, simmering until the mixture reduces (about 20-30 minutes). Finish by adding rosemary and parsley, cooking for another 10 minutes. Set aside.
Coat steaks with olive oil and binder, then season with Steak King seasoning. Allow them to sit briefly. Smoke the steaks at 250°F until they reach an internal temperature of 118°F. After smoking, sear each steak for 60-90 seconds on each side. Let them rest for 8-10 minutes.
First, toast the French Sub Buns. On the bottom bun, spread a layer of the horseradish sauce, followed by 3 slices of Swiss cheese. Add the thinly sliced steak, another 3 slices of Swiss cheese, and top with the prepared French onions. Cap with the top bun.
Place the assembled sandwiches in a preheated oven at 425°F and bake for 8-10 minutes.
Enjoy your sandwich while it's hot!

There you have it, a sandwich that’s more than just a quick bite. It’s a delightful blend of flavors and textures, from the creamy horseradish kick to the savory depth of the French onions, all complemented by the smoky richness of the steak. Every bite is a testament to the magic that happens when simple ingredients come together in the right way.

Next time you’re in the mood for something hearty and satisfying, remember this recipe. Whether it’s for a weekend treat, a special occasion, or just because you deserve it, this sandwich is sure to hit the spot. Happy cooking, and even happier eating!