Ina Garten's Smashed Hamburgers with Caramelized Onions

Ingredients

• 2 tablespoons Canola Oil (high‑heat oil for caramelizing onions)
• 4 cups Red Onion (sliced, about 2 medium sweet red onions)
• 1 teaspoon Granulated Sugar (helps with caramelization)
• 1 tablespoon White Vinegar (deglazes the onions)
• 1.5 teaspoons Dry Mustard Powder (sharp flavor for the beef)
• 1.5 teaspoons Salt (kosher or table salt)
• 0.5 teaspoons Black Pepper (freshly ground preferred)
• 1.25 pounds Ground Beef (80/20) (freshly ground, 20% fat for juiciness)
• 4 ounces Gruyère Cheese (grated, nutty and melts well)
• 4 pieces Potato Rolls (soft rolls; regular hamburger buns work too)

Instructions

1. Slice the onions

   Trim the red onions, halve them, and slice into thin half‑rings to yield about 4 cups.

   Time: PT5M

2. Start caramelizing the onions

   Heat 2 Tbsp canola oil in a large skillet over medium heat. Add the sliced onions, stir, and cook 8‑10 minutes until they soften and begin to turn golden.

   Time: PT10M

   Temperature: medium heat

3. Finish caramelizing and deglaze

   Sprinkle 1 tsp sugar over the onions, lower the heat to low, and continue cooking 12 minutes, stirring occasionally. Add 1 Tbsp white vinegar to deglaze, scraping up browned bits, then cook another minute.

   Time: PT13M

   Temperature: low heat

4. Mix dry seasonings

   In a small bowl combine 1.5 tsp dry mustard powder, 1.5 tsp salt, and 0.5 tsp black pepper.

   Time: PT2M

5. Season and form the beef patties

   Place 1.25 lb ground beef in a mixing bowl, sprinkle the seasoning mixture over it, and gently fold with hands until just combined. Divide into four equal portions and shape each into a 1‑inch‑thick patty without over‑working.

   Time: PT5M

6. Freeze patties briefly

   Place the raw patties on a freezer tray, spacing them apart, and freeze for exactly 15 minutes. This firms the surface for a crisp crust.

   Time: PT15M

7. Preheat the skillet

   Add 1.5 Tbsp canola oil to the cast‑iron skillet and heat over medium‑high heat until shimmering.

   Time: PT2M

   Temperature: medium‑high heat

8. Sear and smash the first side

   Place one frozen patty in the skillet, let it sit for 30 seconds, then press firmly with a spatula or burger press until flat (about ½‑inch thick). Cook 3‑4 minutes until a deep brown crust forms.

   Time: PT4M

   Temperature: medium‑high heat

9. Flip, smash other side, add cheese

   Turn the burger, smash again lightly, and immediately sprinkle a generous handful of grated Gruyère on top. Cover the skillet with a lid for 1‑2 minutes until the cheese melts.

   Time: PT2M

   Temperature: medium‑high heat

10. Assemble the burgers

    Toast the potato rolls lightly if desired, spread any preferred condiments, place a cheese‑topped patty on each bun, top with a generous spoonful of the caramelized onions, and close the sandwich.

    Time: PT2M

Nutrition Facts

Calories

560

Protein

30 g

Carbohydrates

35 g

Fat

30 g

Fiber

2 g

Ingredient Substitutions

• Instead of Canola Oil: grapeseed oil, vegetable oil, avocado oil
• Instead of Red Onion: yellow onion, Vidalia onion
• Instead of Granulated Sugar: honey (use less), maple syrup (use less)
• Instead of White Vinegar: apple cider vinegar, lemon juice
• Instead of Dry Mustard Powder: Dijon mustard (1 tsp), yellow mustard (1 tsp)
• Instead of Salt: sea salt
• Instead of Black Pepper: white pepper
• Instead of Ground Beef (80/20): ground chuck, ground turkey (leaner)
• Instead of Gruyère Cheese: Swiss cheese, Emmental, Gruyère alternative
• Instead of Potato Rolls: regular hamburger buns, brioche buns

Equipment Needed

• Cutting Board
• Chef's Knife
• Mixing Bowl
• Measuring Spoons
• Cast Iron Skillet
• Spatula
• Cheese Grater
• Tongs
• Freezer Tray or Plate

Critical Steps — Do Not Skip

• Caramelize onions slowly to avoid burning.
• Freeze patties for exactly 15 minutes for a crisp crust.
• Press the burger only once per side to retain juices.
• Add Gruyère and cover to melt without overcooking the interior.

Chef Tips from the Video

• Pat the beef dry with paper towels before seasoning for a better sear.
• Press the patty with a sturdy metal spatula and a quick, firm motion—no need to hold the pressure.
• Use a thin‑bottomed cast‑iron skillet; it distributes heat evenly for that classic crust.

Troubleshooting

Storage

Refrigerator: Uncooked seasoned patties can be kept in an airtight container for up to 24 hours; caramelized onions store 3‑4 days.

Freezer: Raw patties freeze well for up to 3 months; re‑freeze after the 15‑minute chill is not recommended.

Room temperature: Assembled burgers should be eaten within 2 hours at room temperature.

Make-Ahead Tips

• Caramelize the onions a day ahead and refrigerate; reheat gently before assembling.
• Form and freeze the raw patties in a single layer; they can go straight from freezer to skillet.
• Grate the Gruyère and store in an airtight container in the fridge.

Frequently Asked Questions