Bacon Sandwich with Caramelized Onions Recipe

Name: Bacon Sandwich with Caramelized Onions Recipe
Prep time: 10 min
Cook time: 30 min
Total time: 40 min
Yield: 4
Cuisine: American
Ingredients: 8 slices of thick-cut bacon; 2 large onions, thinly sliced; 2 tablespoons of olive oil; 1 tablespoon of butter; 8 slices of your favorite bread; Lettuce leaves (optional); Tomato slices (optional); Condiments of your choice (mayonnaise, ketchup, or mustard)

July 18, 2025

- by Jenna

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There’s something undeniably comforting about a perfectly crafted bacon sandwich, especially when it’s loaded with sweet, golden caramelized onions. This recipe takes the classic bacon sandwich to the next level with rich, slow-cooked onions that add depth and a touch of sweetness to every bite. Whether you’re making it for breakfast, lunch, or a late-night snack, this sandwich is sure to satisfy your cravings. Let’s dive in!

Why You’ll Love This Bacon Sandwich with Caramelized Onions Recipe

The Perfect Balance of Sweet and Savory:

The caramelized onions bring a natural sweetness that beautifully complements the salty, crispy bacon, creating a flavor harmony that’s hard to resist.

Simple Ingredients, Big Flavor:

With just a handful of pantry staples, you can whip up a gourmet-style sandwich that feels indulgent without requiring fancy ingredients.

Customizable to Your Taste:

Add fresh veggies, switch up the condiments, or use your favorite bread—this recipe is endlessly adaptable to suit your preferences.

Ingredients for Bacon Sandwich with Caramelized Onions

Thick-cut bacon:

Provides a meaty, crispy texture and rich smoky flavor that’s essential for the sandwich.

Large onions:

When caramelized, they turn sweet and tender, adding depth and complexity to the sandwich.

Olive oil and butter:

Used to sauté the onions, ensuring they cook evenly and develop a rich, golden color.

Your favorite bread:

Choose a sturdy bread like sourdough or ciabatta to hold up against the juicy fillings.

Lettuce and tomato (optional):

Add freshness and a crisp contrast to the rich bacon and onions.

Condiments (mayonnaise, ketchup, or mustard):

Enhance the flavors and add a creamy or tangy element to the sandwich.

(Note: The full list of ingredients with quantities is provided in the recipe card just below.)

Variations

Turkey Bacon Version:

Swap regular bacon for turkey bacon for a leaner option while still enjoying the smoky flavor.

Vegan-Friendly Twist:

Use plant-based bacon and butter, and caramelize the onions in olive oil only for a completely vegan sandwich.

Cheesy Upgrade:

Add a slice of cheddar, Swiss, or pepper jack cheese for a melty, gooey addition.

How to Prepare Bacon Sandwich with Caramelized Onions

Step 1: Caramelizing the Onions

Heat olive oil and butter in a skillet over medium-low heat. Add thinly sliced onions and cook slowly, stirring occasionally, until they turn soft and golden brown (about 20-30 minutes). Patience is key for perfect caramelization!

Step 2: Preparing the Bacon

While the onions cook, fry the bacon in a separate skillet until crispy. Drain on paper towels to remove excess grease.

Step 3: Assembling the Sandwich

Toast the bread, spread your favorite condiments, layer on the caramelized onions and crispy bacon, and add optional lettuce and tomato. Top with another slice of bread, press gently, and enjoy!

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Frying Pan with Teardrop Handle

Perfect for evenly caramelizing onions and achieving crispy bacon without hot spots.

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Stainless Steel Burger Press

Keeps bacon flat while cooking for even crispiness.

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4-Serving Removable Plate Electric Grill and Panini Press

Great for toasting the sandwich to golden perfection after assembling.

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Tips and Tricks

Use a Cast-Iron Skillet for Caramelizing:

A heavy-bottomed skillet distributes heat evenly, preventing onions from burning.

Cook Bacon in the Oven:

For perfectly crispy bacon with less mess, bake it at 400°F (200°C) for 15-20 minutes on a lined baking sheet.

Make Extra Caramelized Onions:

They keep well in the fridge for up to 5 days and can be used in omelets, pizzas, or burgers.

How to Serve

Pair with a Side of Crispy Fries:

Serve this sandwich with homemade or store-bought fries for a classic diner-style meal.

Add a Fresh Salad:

Balance the richness of the sandwich with a light green salad dressed in vinaigrette.

Enjoy with a Cold Beverage:

A crisp beer, iced tea, or lemonade complements the flavors perfectly.

Make-Ahead and Storage

Store Components Separately:

Keep caramelized onions and cooked bacon in airtight containers in the fridge for up to 3 days. Assemble the sandwich fresh when ready to eat.

Freeze Cooked Bacon:

Place cooled bacon in a freezer bag and freeze for up to 2 months. Reheat in a skillet or microwave.

Reheat Onions Gently:

Warm caramelized onions in a skillet over low heat or in the microwave with a splash of water to prevent drying out.

FAQ

1. Can I use pre-cooked bacon?

Yes, but freshly cooked bacon will have better texture and flavor. If using pre-cooked, warm it slightly before assembling.

2. How do I speed up caramelizing onions?

Add a pinch of sugar or splash of balsamic vinegar to help speed up the browning process, but avoid high heat to prevent burning.

3. What’s the best bread for this sandwich?

A sturdy bread like sourdough, ciabatta, or a thick-cut whole grain works best to hold the fillings without getting soggy.

There you have it—a bacon sandwich with caramelized onions that’s simple yet packed with flavor. Whether you’re making it for a lazy weekend brunch or a quick weeknight dinner, this sandwich is guaranteed to hit the spot. Happy cooking!