I can never resist the way crisp bacon and jammy caramelized onions turn a simple sandwich into something wildly craveable. This is the kind of bacon sandwich that disappears fast, then lingers in your mind all day.
I’m obsessed with this bacon sandwich because it hits every craving I have at once: salty, sweet, crunchy, messy, and completely unapologetic. Thick-cut smoked bacon brings that deep, smoky snap I want, while yellow onions turn sweet and jammy enough to make the whole thing feel borderline reckless.
I love how each bite has contrast instead of just being heavy for the sake of it. But let’s be honest, the bacon is still the reason I keep thinking about it hours later.
The onions just make it impossible to stop. A sandwich with attitude.
And I’m absolutely here for it.
Ingredients
- Thick-cut smoked bacon brings the salty crunch, and yeah, it’s the main event.
- Yellow onions turn sweet and jammy, making the sandwich feel cozy and diner-level good.
- Butter gives the onions richness, because dry onions are honestly kind of sad.
- Olive oil helps everything cook smoothly without the butter getting too bossy.
- Sugar nudges the onions sweeter, but it doesn’t make them taste like candy.
- Balsamic vinegar adds a tangy little kick that keeps things from feeling too heavy.
- Kosher salt wakes up the bacon, onions, bread, basically every bite.
- Black pepper adds a tiny bite, like the sandwich needed some attitude.
- Sturdy bread or crusty rolls hold the messy good stuff without falling apart.
- Mayonnaise makes it creamy, a little tangy, and totally sandwich-shop style.
- Toasting butter gives the bread golden edges and that snacky crunch you’ll love.
- Sharp cheddar is optional, but Plus, it melts into salty, gooey comfort.
Ingredient Quantities
- 8 slices thick-cut smoked bacon
- 2 large yellow onions, thinly sliced
- 2 tablespoons unsalted butter
- 1 tablespoon extra virgin olive oil
- 1 teaspoon granulated sugar
- 1 teaspoon balsamic vinegar
- 1/2 teaspoon kosher salt, plus more to taste
- 1/4 teaspoon freshly ground black pepper
- 4 slices sturdy sandwich bread or 2 crusty rolls
- 2 tablespoons mayonnaise
- 2 tablespoons butter for toasting the bread
- 4 slices sharp cheddar cheese (optional)
How to Make this
1. Peel and thinly slice the yellow onions. Melt 2 tablespoons unsalted butter with 1 tablespoon olive oil in a large skillet over medium-low heat.
2. Add the sliced onions, 1 teaspoon granulated sugar, 1/2 teaspoon kosher salt and 1/4 teaspoon freshly ground black pepper. Stir to coat and spread in an even layer.
3. Cook the onions slowly over medium-low heat, stirring every 5 to 7 minutes, until deeply golden and sweet, about 30 to 40 minutes.
4. During the last 5 minutes of caramelizing, stir in 1 teaspoon balsamic vinegar, then taste and adjust salt and pepper if needed. Remove onions from the pan and keep warm.
5. While the onions cook, cook the 8 slices thick-cut smoked bacon in a separate skillet over medium heat until browned and crispy, or bake on a rimmed sheet at 400 F until crisp, turning once. Drain on paper towels.
6. Spread 2 tablespoons mayonnaise on one side of each of the 4 bread slices or on the insides of the 2 crusty rolls. Butter the other side of the bread with the 2 tablespoons butter for toasting.
7. Heat a clean skillet or griddle over medium heat. Place the bread buttered-side down and toast until golden. If using cheese, add 1 slice sharp cheddar to the mayo side while the bread is in the pan so the cheese melts.
8. Assemble each sandwich by layering bacon slices, a generous portion of caramelized onions, and final bread slice with mayo side down. Add extra salt or pepper to taste.
9. Press gently, slice and serve immediately while warm.
Equipment Needed
1. Large heavy skillet (for caramelizing onions)
2. Second skillet or rimmed baking sheet (for cooking bacon)
3. Cutting board
4. Chef’s knife
5. Wooden spoon or heatproof spatula
6. Pair of tongs
7. Measuring spoons
8. Butter knife or small offset spatula (for spreading mayo and butter)
9. Paper towels (for draining bacon)
FAQ
Best Bacon Sandwich With Caramelized Onions Recipe Substitutions and Variations
- Bacon
- Pancetta, sliced thick for similar fat and salt
- Canadian bacon or back bacon for leaner, ham like flavor
- Smoked turkey bacon for lower fat and smoky taste
- Yellow onions
- Sweet onions like Vidalia for milder, sweeter caramelization
- Red onions for a sharper, slightly fruity note
- Shallots for a more delicate, nuanced sweetness
- Sturdy sandwich bread or crusty rolls
- Sourdough for tang and chew
- Whole grain bread for nuttier flavor and more texture
- Sharp cheddar cheese (optional)
- Gruyère for nutty, melty richness
- Smoked Gouda for extra smoky depth
- Fontina for creamy melt without overpowering
Pro Tips
1. Take your time caramelizing the onions. Low and slow is the secret to deep, jammy sweetness, and stirring only every 5 to 7 minutes helps them brown evenly without turning mushy.
2. Use a combination of butter and oil so the butter adds flavor while the oil raises the smoke point. If any bits start to stick, lower the heat and scrape them up gently with a wooden spatula so you don’t burn the sugars.
3. Add the balsamic vinegar right near the end, then let it bubble briefly to concentrate and marry with the onions. Taste and adjust salt after adding it since acidity can change the seasoning balance.
4. For perfectly crisp bacon with less mess, bake it on a rimmed sheet in a single layer; if you prefer skillet bacon, start in a cold pan and cook over medium so the fat renders slowly. Either way, drain on paper towels and blot lightly to avoid soggy bread.
5. Toast the bread butter-side down until golden, then add mayo and cheese to the non-toasted face so the mayo keeps things moist and the cheese melts into the warm bacon and onions. If you want to prep ahead, store onions and bacon separately and assemble just before serving so textures stay bright.
Best Bacon Sandwich With Caramelized Onions Recipe
I can never resist the way crisp bacon and jammy caramelized onions turn a simple sandwich into something wildly craveable. This is the kind of bacon sandwich that disappears fast, then lingers in your mind all day.
2
servings
1298
kcal
Equipment: 1. Large heavy skillet (for caramelizing onions)
2. Second skillet or rimmed baking sheet (for cooking bacon)
3. Cutting board
4. Chef’s knife
5. Wooden spoon or heatproof spatula
6. Pair of tongs
7. Measuring spoons
8. Butter knife or small offset spatula (for spreading mayo and butter)
9. Paper towels (for draining bacon)
Ingredients
8 slices thick-cut smoked bacon
2 large yellow onions, thinly sliced
2 tablespoons unsalted butter
1 tablespoon extra virgin olive oil
1 teaspoon granulated sugar
1 teaspoon balsamic vinegar
1/2 teaspoon kosher salt, plus more to taste
1/4 teaspoon freshly ground black pepper
4 slices sturdy sandwich bread or 2 crusty rolls
2 tablespoons mayonnaise
2 tablespoons butter for toasting the bread
4 slices sharp cheddar cheese (optional)
Directions
- Peel and thinly slice the yellow onions. Melt 2 tablespoons unsalted butter with 1 tablespoon olive oil in a large skillet over medium-low heat.
- Add the sliced onions, 1 teaspoon granulated sugar, 1/2 teaspoon kosher salt and 1/4 teaspoon freshly ground black pepper. Stir to coat and spread in an even layer.
- Cook the onions slowly over medium-low heat, stirring every 5 to 7 minutes, until deeply golden and sweet, about 30 to 40 minutes.
- During the last 5 minutes of caramelizing, stir in 1 teaspoon balsamic vinegar, then taste and adjust salt and pepper if needed. Remove onions from the pan and keep warm.
- While the onions cook, cook the 8 slices thick-cut smoked bacon in a separate skillet over medium heat until browned and crispy, or bake on a rimmed sheet at 400 F until crisp, turning once. Drain on paper towels.
- Spread 2 tablespoons mayonnaise on one side of each of the 4 bread slices or on the insides of the 2 crusty rolls. Butter the other side of the bread with the 2 tablespoons butter for toasting.
- Heat a clean skillet or griddle over medium heat. Place the bread buttered-side down and toast until golden. If using cheese, add 1 slice sharp cheddar to the mayo side while the bread is in the pan so the cheese melts.
- Assemble each sandwich by layering bacon slices, a generous portion of caramelized onions, and final bread slice with mayo side down. Add extra salt or pepper to taste.
- Press gently, slice and serve immediately while warm.
Notes
- Below you’ll find my best estimate of this recipe’s nutrition facts. Treat the numbers as a guide rather than a rule—great food should nourish both body and spirit. Figures are approximate, and the website owner assumes no liability for any inaccuracies in this recipe.
Nutrition Facts
- Serving Size: 410g
- Total number of serves: 2
- Calories: 1298kcal
- Fat: 108g
- Saturated Fat: 50g
- Trans Fat: 1g
- Polyunsaturated: 7g
- Monounsaturated: 45g
- Cholesterol: 224mg
- Sodium: 1735mg
- Potassium: 1062mg
- Carbohydrates: 47g
- Fiber: 5g
- Sugar: 11g
- Protein: 64g
- Vitamin A: 760IU
- Vitamin C: 11mg
- Calcium: 464mg
- Iron: 3.5mg
