These French Onion Beef Sliders are mini sandwiches packed with tender beef and rich onion flavor. Topped with gooey cheese and served on soft buns, they’re perfect for sharing!
What’s better than one slider? A whole plate of them! I love to serve these at parties, and they disappear faster than I can say “extra onions”! 😄
These sliders are quick to make, and I enjoy making them ahead of time. Just warm them up before serving for a tasty treat everyone will love!
Key Ingredients & Substitutions
Yellow Onions: These are essential for caramelizing, bringing a natural sweetness to your sliders. If yellow onions aren’t available, white onions work too, but they’ll be slightly sharper in flavor.
Ground Beef: An 80/20 blend is great for these sliders because it keeps them juicy. If you’re looking for a leaner option, 90/10 works as well, but be careful not to overcook them.
Gruyère Cheese: This cheese adds a delightful nutty flavor. If you can’t find Gruyère, feel free to substitute with Swiss cheese or even provolone for a milder taste.
Slider Buns: I love using soft, slightly sweet buns. For a healthier twist, you could opt for whole wheat or pretzel buns for added texture!
Thyme: Fresh thyme gives a lovely herbaceous note. If you only have dried thyme, use half the amount since dried herbs are more concentrated.
How Do I Caramelize Onions Perfectly?
Caramelizing onions takes time and patience, but it’s so worth it! The aim is to coax out their natural sugars, creating a sweet, golden topping for your sliders.
- Start with medium heat and add olive oil to your skillet.
- Add sliced onions, a bit of salt, and sugar. This helps the onions soften and caramelize.
- Cook slowly, stirring occasionally. Avoid rushing it with high heat, as this can burn the onions.
- Cook for about 25-30 minutes, until they are golden brown and soft. Add thyme and pepper in the last few moments for extra flavor.
Don’t skip this step; well-caramelized onions take these sliders to the next level!
How to Make French Onion Beef Sliders?
Ingredients You’ll Need:
For the Sliders:
- 2 tablespoons olive oil
- 3 large yellow onions, thinly sliced
- 1 teaspoon sugar
- 1 teaspoon salt, divided
- 1/2 teaspoon black pepper
- 1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried thyme)
- 1 1/2 pounds ground beef (80/20)
- 12 slider buns (soft, slightly sweet)
- 6 ounces Gruyère cheese, sliced or shredded
- 1/2 cup beef broth or French onion soup (optional for extra flavor/moisture)
- Butter, for toasting buns
- Fresh thyme sprigs, for garnish (optional)
How Much Time Will You Need?
This recipe takes about 15-20 minutes for preparation and approximately 30-35 minutes for cooking. You’ll have a total of about 50-55 minutes from start to finish, making these sliders a delicious option for a quick dinner or a party snack!
Step-by-Step Instructions:
1. Caramelize the Onions:
First, heat the olive oil in a large skillet over medium heat. Add the thinly sliced onions along with the sugar and 1/2 teaspoon of salt. Stir them occasionally as they cook, allowing them to become golden brown and caramelized. This will take about 25-30 minutes. Near the end of this cooking time, sprinkle in the thyme and black pepper to add flavor. Once done, remove the skillet from the heat and set the onions aside.
2. Prepare the Beef Patties:
In a bowl, take the ground beef and mix in the remaining 1/2 teaspoon salt and black pepper. Be gentle when mixing—overworking the beef can make the patties tough! Form the mixture into 12 small slider-sized patties. Make sure they are slightly larger than your buns, as they will shrink a bit while cooking.
3. Cook the Patties:
Now it’s time to cook the patties! Heat a grill or skillet over medium-high heat. Cook each patty for about 3-4 minutes on one side, then flip and cook for another 3-4 minutes until they’re fully cooked but still juicy. You want them to be nice and tender!
4. Add the Cheese:
During the last minute of cooking, place a slice or a generous handful of Gruyère cheese on each patty. Cover the skillet or grill momentarily to help the cheese melt perfectly on top of the beef.
5. Toast the Buns:
While the patties are cooking, butter the cut sides of your slider buns. Toast them on a skillet or griddle until they are golden brown. This adds a delightful crunch!
6. Assemble the Sliders:
Time to put it all together! Take the bottom half of each toasted bun and place a patty with melted cheese on it. Top each patty with a generous spoonful of the caramelized onions. For extra flavor, consider drizzling a little beef broth or French onion soup over the onions (this is optional but delicious!).
7. Serve and Enjoy:
Cover each slider with the top bun and garnish with a sprig of fresh thyme if you like. Serve these tasty sliders warm, and watch them disappear!
These French Onion Beef Sliders are a delicious combination of sweet, caramelized onions, savory beef, and melted cheese all packed into soft slider buns, making them perfect for any occasion!
Can I Use Different Types of Onions?
Absolutely! While yellow onions are ideal for their sweetness, you can also use white onions or even sweet onions like Vidalia for a milder flavor. Just keep in mind that red onions may have a sharper taste and won’t caramelize as sweetly.
Can I Make These Sliders Ahead of Time?
Yes, you can prepare the caramelized onions and form the beef patties ahead of time! Store the onions in an airtight container in the fridge for up to 3 days. For the patties, shape them and keep them on a parchment-lined tray in the fridge until you’re ready to cook them. Just remember to cook them fresh for the best flavor!
How Should I Store Leftover Sliders?
Store any leftover sliders in airtight containers in the fridge for up to 3 days. To reheat, microwave them for a few seconds until warmed through or use an oven to maintain the bun’s texture—just wrap them in foil and heat at 350°F until warmed.
Can I Make These Sliders Vegetarian?
Definitely! You can substitute the beef with veggie burgers or a mixture of lentils and mushrooms for a hearty vegetarian version. Just ensure you season them well for that delicious flavor punch!