I made these on a whim one evening when I had a wedge of brie that needed using up and ground beef in the fridge, and they’ve been a regular request ever since. The combination of that crispy smashed patty, melting brie, and slow-cooked jammy onions is genuinely better than most restaurant burgers I’ve had. Slider-sized means everyone gets the right ratio of everything in one bite, and the whole thing is on the table in under 35 minutes.
The caramelized onions are the only thing that takes any patience – give them a full 20 minutes on low heat and don’t rush them. Everything else is fast.
If you’re making these for a crowd, the ham and cheese sliders are a great second tray to put out alongside – different flavor profile, same easy format.
Servings: 4 sliders (double or triple for a crowd)
Prep Time: 15 minutes
Cook Time: 20 minutes
Total Time: ~35 minutes
Skill Level: Easy
Flavor Profile: Savory · Rich · Slightly Sweet · Gooey
Why These Sliders Work
- Smash burgers = crispy edges + juicy center
- Brie brings buttery, melty luxury — way beyond cheddar
- Caramelized onions add sweet, deep flavor that balances the beef and cheese
- Sliders are small but mighty — and perfect for sharing (or not sharing, we don’t judge)
For the full spread treatment, the charcuterie nachos make a brilliant addition to the same table.
Ingredients
For the Patties
- 400g (about 14 oz) ground beef (80/20 or higher fat for best results)
- Salt and freshly cracked black pepper
- 1 tsp garlic powder (optional)
- 1 tsp Worcestershire sauce (optional)
- Neutral oil or butter, for frying
For the Caramelized Onions
- 1 large yellow onion, thinly sliced
- 1 tbsp butter
- 1 tsp olive oil
- Pinch of salt
- Optional: ½ tsp sugar for quicker caramelizing
- Optional: splash of balsamic or white wine vinegar at the end
For Assembling
- 4–6 slices brie cheese, rind on or off
- 4 slider buns or mini brioche buns
- Butter, for toasting buns
- Optional extras: arugula, Dijon mustard, aioli, crispy shallots
Method
Step 1: Caramelize the Onions
- Heat butter and olive oil in a nonstick skillet over medium-low heat.
- Add sliced onions and a pinch of salt. Stir to coat.
- Cook low and slow for 15–20 minutes, stirring every few minutes, until onions are soft, golden brown, and jammy.
- Optional: Stir in a splash of balsamic vinegar or a pinch of sugar for extra depth.
- Set aside and keep warm.
Step 2: Prep the Patties
- Divide your ground beef into 4 equal balls (about 100g or 3.5 oz each).
- Keep them loose — don’t pack tightly. This helps with that crisp smash.
- Season lightly with salt, pepper, and garlic powder if using.
Step 3: Smash & Sear
- Heat a heavy-bottomed skillet or cast iron pan until very hot — almost smoking.
- Add a little oil and place 1–2 balls of beef in the pan (don’t overcrowd).
- Immediately smash them flat with a spatula or burger press (use parchment paper between spatula and meat to prevent sticking).
- Cook undisturbed for 2–3 minutes, until the edges are deeply browned and crisp.
- Flip, top each patty with a slice of brie, and cook another 1–2 minutes until cheese starts to melt.
- Remove from pan and repeat with remaining patties.
Step 4: Toast the Buns
- Wipe the skillet clean and melt a little butter.
- Toast the cut sides of the slider buns until golden and crisp.
Step 5: Assemble the Sliders
- Spread Dijon mustard or aioli on bottom buns (optional but delicious).
- Place brie-topped patty on each bun.
- Add a scoop of caramelized onions on top.
- Optionally layer with arugula or crispy shallots.
- Crown with the top bun and secure with a skewer if needed.
🔥 Bonus move: Brush the tops of the buns with melted butter and a pinch of sea salt before serving.
🔍 Nutritional Info (Per Slider – Approximate)
| Nutrient | Amount |
|---|---|
| Calories | 420–500 kcal |
| Protein | 20–24 g |
| Fat | 25–30 g |
| Carbs | 25–30 g |
| Sodium | 500–600 mg |
Will vary based on bun size, cheese quantity, and sauces used.
“If you want a second sandwich recipe in the same session, the pickle-brined fried chicken sandwich uses a completely different technique and is worth making back to back.”
Serving Suggestions
- Serve with:
- Skinny fries or sweet potato wedges
- Arugula salad with lemon vinaigrette
- Pickles or slaw on the side
- Make it a board! Lay out sliders on a platter with extra onions, sauces, and napkins — they’re messy in the best way.
For a vegetarian option that works on the same board, the hot honey halloumi sliders are just as crowd-pleasing.
Storage & Reheating
- Caramelized onions can be made ahead and refrigerated for up to 5 days.
- Cooked patties keep for 2–3 days in the fridge; reheat in a pan or low oven.
- Assembled sliders are best fresh but can be reheated (open-faced) in a 160°C (325°F) oven for 10 minutes.
Smash Burger Sliders with Brie & Caramelized Onions
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Ingredients
Method
- Heat butter and olive oil in a nonstick skillet over medium-low heat.
- Add sliced onions and a pinch of salt. Stir to coat.
- Cook low and slow for 15–20 minutes, stirring every few minutes, until onions are soft, golden brown, and jammy.
- Optional: Stir in a splash of balsamic vinegar or a pinch of sugar for extra depth.
- Set aside and keep warm.
- Divide your ground beef into 4 equal balls (about 100g or 3.5 oz each).
- Keep them loose — don’t pack tightly. This helps with that crisp smash.
- Season lightly with salt, pepper, and garlic powder if using.
- Heat a heavy-bottomed skillet or cast iron pan until very hot — almost smoking.
- Add a little oil and place 1–2 balls of beef in the pan (don’t overcrowd).
- Immediately smash them flat with a spatula or burger press (use parchment paper between spatula and meat to prevent sticking).
- Cook undisturbed for 2–3 minutes, until the edges are deeply browned and crisp.
- Flip, top each patty with a slice of brie, and cook another 1–2 minutes until cheese starts to melt.
- Remove from pan and repeat with remaining patties.
- Wipe the skillet clean and melt a little butter.
- Toast the cut sides of the slider buns until golden and crisp.
- Spread Dijon mustard or aioli on bottom buns (optional but delicious).
- Place brie-topped patty on each bun.
- Add a scoop of caramelized onions on top.
- Optionally layer with arugula or crispy shallots.
- Crown with the top bun and secure with a skewer if needed.
- Bonus move: Brush the tops of the buns with melted butter and a pinch of sea salt before serving.
Nutrition
Notes
Serving Suggestions
- Serve with:
- Skinny fries or sweet potato wedges
- Arugula salad with lemon vinaigrette
- Pickles or slaw on the side
- Make it a board! Lay out sliders on a platter with extra onions, sauces, and napkins — they’re messy in the best way.
Storage & Reheating
- Caramelized onions can be made ahead and refrigerated for up to 5 days.
- Cooked patties keep for 2–3 days in the fridge; reheat in a pan or low oven.
- Assembled sliders are best fresh but can be reheated (open-faced) in a 160°C (325°F) oven for 10 minutes.
