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• What Is a Smash Burger?
• Tips for Cooking and Prepping
• Recipe Variations and Substitutes
• Serving Suggestions
• Storing, Make-Ahead, and Freezing Tips
• FAQs
• Easy Ground Beef Smash Burgers with Caramelized Onions Recipe

If you’re craving a juicy, restaurant-style burger without the restaurant price tag, these ground beef smash burgers are about to become your new weeknight favorite. With crispy caramelized edges, sweet melty onions, and gooey American cheese, they taste like something from a fancy burger joint but cost a fraction of the price to make at home.

What Is a Smash Burger?

A smash burger is exactly what it sounds like: a ball of ground beef that gets smashed flat on a hot skillet or griddle, creating a super thin patty with maximum surface area. That extra surface area means more direct contact with the hot pan, which translates into a deeply caramelized, crispy crust on the outside while the inside stays juicy and tender.

Smash burgers became wildly popular thanks to fast-casual burger chains, but the beauty of this technique is that you can easily recreate it at home with nothing more than a skillet and a sturdy spatula. Paired with sweet, slow-cooked caramelized onions and a slice of classic American cheese, this version turns basic ground beef into something that tastes indulgent while still being incredibly cheap to make.

Tips for Cooking and Prepping

#1: Use an 80/20 ground beef blend

Ground beef with 80% lean meat and 20% fat gives you the best balance of flavor, juiciness, and crispy edges. Leaner beef will dry out and won’t caramelize as well when smashed.

#2: Buy a bigger pack of ground beef and freeze portions

Ground beef is often cheaper per pound when purchased in family-size or bulk packs. Divide it into 3-4 ounce balls and freeze them individually so you always have smash burger portions ready to go without waste.

#3: Don’t overwork the meat

Gently shape the beef into loose balls without packing or kneading it. Overworking the meat makes for a dense, tough patty instead of a light, tender one.

#4: Smash immediately after the beef hits the hot pan

Press the beef ball flat within the first 10-15 seconds of it touching the skillet using a sturdy spatula or bacon press. Waiting too long means you lose the raw surface contact needed for that deep golden crust.

#5: Caramelize a big batch of onions at once

Onions are cheap and caramelize best low and slow, so make extra and store the leftovers in the fridge for topping future burgers, tacos, or scrambled eggs.

#6: Salt the patties right before cooking, not before

Salting ground beef too early draws out moisture and can make the patties tougher, so season them just before they hit the hot pan for the juiciest results.

Recipe Variations and Substitutes

Swap American cheese for cheddar, pepper jack, or Colby if that’s what you have on hand, and use yellow, white, or even red onions for the caramelized topping depending on what’s cheapest that week. Ground turkey or a beef-and-pork blend can also stand in for ground beef in a pinch, though the classic all-beef version delivers the best crust and flavor.

Serving Suggestions

Serve these smash burgers on soft white or brioche-style buns with classic fixings like pickles, ketchup, and mustard, alongside oven-baked fries, a simple side salad, or leftover cut-up veggies to round out the meal. For an easy budget-friendly side, homemade oven fries from a bag of potatoes cost far less than takeout.

Storing, Make-Ahead, and Freezing Tips

Cooked patties keep well in an airtight container in the fridge for up to 3 days and reheat nicely in a skillet or microwave. Caramelized onions can be made up to 5 days ahead and stored separately, and raw beef portions can be frozen for up to 3 months for quick future burger nights.

FAQs

Do I need a griddle to make smash burgers?

No, a regular cast iron skillet or heavy nonstick pan works just as well as a griddle, as long as it gets very hot before you add the beef.

Why aren’t my smash burgers getting crispy?

This usually happens if the pan isn’t hot enough or the beef isn’t smashed thin and fast enough, so preheat your skillet until it’s very hot and press the patties flat within the first few seconds of cooking.

Can I make caramelized onions ahead of time?

Yes, caramelized onions actually taste even better after resting, so feel free to make a big batch a few days in advance and reheat a spoonful whenever you’re ready to build your burgers.

What’s the best cheap cheese for smash burgers?

Classic deli-style American cheese slices are inexpensive, melt beautifully, and give that signature gooey diner-style texture that pairs perfectly with smash burgers.

Can I use frozen ground beef for this recipe?

Yes, just thaw it fully in the refrigerator overnight before shaping it into balls, since starting with cold, fresh (not still-frozen) beef helps it smash and crisp up properly.

Easy Ground Beef Smash Burgers with Caramelized Onions Recipe

Prep time: 15 min | Cook time: 25 min | Total time: 40 min | Servings: 4

Ingredients

For the Caramelized Onions

• 2 tablespoons butter or vegetable oil
• 2 large yellow onions, thinly sliced
• 1/2 teaspoon salt
• 1/2 teaspoon sugar (optional, helps caramelization)

For the Smash Burgers

• 1 1/2 lbs ground beef (80/20 blend)
• 1 teaspoon salt, divided
• 1/2 teaspoon black pepper
• 8 slices American cheese
• 4 hamburger buns
• 1 tablespoon vegetable oil, for the pan
• Ketchup, mustard, and pickles, for serving

Instructions

1. Heat butter or oil in a large skillet over medium-low heat. Add the sliced onions and salt, and cook slowly, stirring occasionally, for 20-25 minutes until deeply golden and soft. Stir in the sugar if using, then remove from heat and set aside.
2. While the onions cook, divide the ground beef into 4 equal portions (about 6 ounces each) and gently shape into loose balls without packing the meat tightly.
3. Heat a separate large cast iron skillet or heavy pan over high heat with the vegetable oil until very hot and just starting to smoke.
4. Place a beef ball in the skillet and immediately press it flat with a sturdy spatula or bacon press until it’s about 1/4 inch thick and 5-6 inches wide.
5. Season the top of the patty with a pinch of salt and pepper, and cook for 2-3 minutes until a deep golden-brown crust forms on the bottom.
6. Flip the patty, immediately top with a slice of American cheese, and cook for another 1-2 minutes until the cheese melts and the beef is cooked through.
7. Repeat with the remaining beef portions, wiping the pan and re-oiling between batches if needed.
8. Toast the buns lightly in the same skillet for extra flavor, then build the burgers with a smashed patty, a generous spoonful of caramelized onions, and your favorite condiments.
9. Serve immediately while warm and enjoy.

For extra-cheesy burgers, stack two smash patties with cheese between them for a double smash burger. Leftover caramelized onions freeze well for up to 2 months.