This sourdough pesto grilled cheese is the gooey, golden, flavor-packed sandwich you didn’t know you needed — loaded with fresh mozzarella, crispy bacon, sun-dried tomatoes, and herby pesto, all toasted to perfection on thick sourdough bread.
Okay, real talk — I made this on a whim one afternoon when I had leftover pesto and half a block of mozzarella staring at me from the fridge, and it completely ruined regular grilled cheese for me forever.
Like, how was I ever satisfied with just cheddar and bread? This sourdough pesto grilled cheese is the kind of sandwich that makes you close your eyes on the first bite.
Table of Contents
What Makes This Sandwich So Special
This isn’t your average grilled cheese. We’re talking thick, crunchy sourdough, pockets of melty mozzarella, smoky bacon bits, tangy sun-dried tomatoes, and a generous slather of pesto that basically does all the heavy lifting flavor-wise.
It hits every note — salty, herby, rich, a little tangy — and it comes together in under 15 minutes. It’s one of those foods with pesto that proves pesto deserves to be on everything.
Whether you’re making a quick weeknight dinner, looking for healthy grilled sandwiches that still feel indulgent, or even packing up food to bring to a picnic (yes, this travels surprisingly well), this recipe has got you covered.
Sourdough Pesto Grilled Cheese
Equipment
- Frying pan
- spatula
Ingredients
Main Ingredients
- 8 slices sourdough bread thick slices
- 3 balls fresh mozzarella sliced thin
- butter for grilling
- 4 tbsp pesto
- 4 strips bacon cooked and crumbled
- 8 sun-dried tomatoes finely chopped
Instructions
- Place two slices of sourdough in a cold frying pan. Butter the top sides, then flip them so the buttered sides are facing down.
- Layer mozzarella slices evenly on each piece of bread. Add pesto on top, then sprinkle sun-dried tomatoes and crumbled bacon.
- Add another layer of mozzarella, then top with the second slice of bread to form a sandwich. Butter the top side and gently press down.
- Turn heat to medium and cook until the bottom is golden brown. Flip carefully and cook the other side until golden and the cheese is melted.
- Remove from heat, let rest briefly, then slice and serve warm.
Notes
Ingredients
Here’s everything you’ll need. Nothing weird, I promise.
| Category | Ingredient |
|---|---|
| Bread | 8 thick slices sourdough bread |
| Cheese | 3 balls fresh mozzarella (125g each), sliced thin |
| Spread | Butter, for grilling (Kerrygold Cultured Butter is chef’s kiss) |
| Sauce | 4 tbsp pesto (homemade or good store-bought like Barilla) |
| Fillings | 4 strips bacon, cooked and crumbled |
| Fillings | 8 sun-dried tomatoes, finely chopped |
A note on the pesto: If you’ve got a jar of Barilla in the pantry, that works beautifully here. But if you want to go homemade, check out this Mexican white cheese dip recipe for inspiration on how easy homemade sauces can be — then apply that same energy to blending up your own basil pesto. You won’t regret it.
Step-by-Step Instructions
Step 1: Set Up Your Bread (Pan Off the Heat!)
Lay two slices of sourdough flat in your frying pan — and keep the heat OFF for now. This is important. You want to build the sandwich in the pan so you don’t have to do a chaotic transfer later.
Spread a generous layer of butter on the top side of each slice, then flip them butter-side down. Now the buttered side is face-down in the pan, ready to get golden and crispy when the heat comes on.
Tip: Don’t be shy with the butter. This is not the moment for restraint. Kerrygold or any good cultured butter gives you that gorgeous golden crust you’re looking for.
If your pan is big enough, go ahead and prep four slices at once for two sandwiches. Efficiency is beautiful.
Step 2: Layer Up the Good Stuff
Now for the fun part. On each bread slice, lay down 3–4 thin slices of fresh mozzarella. You want it distributed evenly so every bite has that melt factor.
Next, add a heaped tablespoon of pesto right on top of the mozzarella. Spread it gently — it’s going to seep into everything as it heats up and it’s incredible. This step is honestly why sourdough pesto grilled cheese beats every other sandwich in the game.
Scatter your finely chopped sun-dried tomatoes and crumbled bacon over the pesto. The sun-dried tomatoes add this jammy, concentrated tomato flavor that pairs so well with the herby pesto — don’t skip them.
Finish with another layer of mozzarella slices on top of the fillings. Yes, a second cheese layer. This is what holds everything together and gives you that extra-gooey center. Then place your second slice of bread on top to close the sandwich.
Step 3: Butter the Top and Press Down
With the sandwich assembled, gently press down with your palm to compact everything. This helps keep your fillings inside where they belong (instead of escaping dramatically across the pan).
Spread butter on the top side of each sandwich — this is the side that’ll get flipped onto the pan later. Both sides need butter for that even, golden toast all around.
Step 4: Cook Low and Slow
Now you can turn the heat on — medium is your sweet spot here. Let the pan warm up gradually with the sandwiches already in it. This slow heat-up is what lets the cheese start melting from the bottom before the bread gets too dark.
Cook until the bottom is golden brown (you’ll hear that satisfying sizzle), then carefully flip and cook the other side. The goal is a deep golden crust on both sides with cheese that’s completely melted through the middle.
Don’t rush it on high heat. You’ll end up with burned bread and cold cheese in the center, and that’s a tragedy nobody needs.
Step 5: Rest, Slice, and Dig In
Once both sides are golden and gorgeous, take the sandwiches off the heat. Let them sit for just a minute — I know it’s hard, but this helps everything settle so the cheese doesn’t just pour out the second you cut it.
Slice diagonally (obviously — triangles taste better, it’s science), and enjoy your sourdough pesto grilled cheese while it’s still warm and melty. Pair it with a simple salad or some tomato soup and you’ve got a full meal that feels like a proper treat.
Expert Tips, Variations & Troubleshooting
Tips for the Best Results
Use thick sourdough slices. Thin bread will go soggy under all that filling. A good thick-cut sourdough holds its structure and gets beautifully crispy on the outside while staying soft inside.
Slice the mozzarella thin. Thick chunks won’t melt evenly. Thin slices = even melt = gooey perfection throughout. If your mozzarella is extra wet, pat it dry with a paper towel before using it.
Cook on medium, not high. I know it’s tempting to crank the heat to speed things up, but medium heat is what gives you that even golden crust without burning the bread before the cheese melts.
Fun Variations to Try
Go meat-free: Skip the bacon and add roasted red peppers or sliced olives instead. Still an amazing sandwich — one of the best healthy grilled sandwiches you can make with just a few swaps.
Add some heat: A pinch of red chili flakes on top of the pesto layer adds a gentle kick that plays really nicely with the richness of the cheese.
Make it a picnic sandwich: This is genuinely great food to bring to a picnic. Let it cool completely, wrap tightly in parchment, and slice before heading out. It holds up better than you’d think, and everyone will want to know what you brought.
Try different pesto: Classic basil pesto is the move here, but sun-dried tomato pesto or kale pesto also work really well and make it feel a little different each time.
Troubleshooting
Bread burning before cheese melts? Your heat is too high. Lower it and give it more time — patience pays off here.
Cheese not melting? Your slices might be too thick, or the heat is too low. Medium heat and thin mozzarella slices are key.
Sandwich falling apart? Press it down firmly before cooking and make sure that second layer of mozzarella is doing its job as the “glue” holding the fillings together.
Storage & Reheating
| Method | How Long | Notes |
|---|---|---|
| Room temperature | Up to 2 hours | Wrap in parchment for picnics |
| Refrigerator | Up to 2 days | Store in an airtight container |
| Freezer | Not recommended | Mozzarella doesn’t freeze well here |
To reheat: Skip the microwave — it makes the bread sad and chewy. Instead, pop it in a dry pan over medium-low heat for a few minutes per side, or use an air fryer at 350°F for about 3–4 minutes. It comes back to life beautifully.
No-waste tip: Leftover pesto? Use it as a dip for veggies, toss it with pasta, or swirl it into scrambled eggs. If you’ve got extra bacon, crumble it over a salad or these chicken street tacos for an extra little something.
Nutritional Information (Per Sandwich, Approximate)
| Nutrient | Amount |
|---|---|
| Calories | ~620 kcal |
| Protein | ~28g |
| Fat | ~38g |
| Carbohydrates | ~42g |
| Fiber | ~3g |
| Sodium | ~890mg |
Values are estimates and will vary based on specific brands and portion sizes.
Sourdough Pesto Grilled Cheese FAQs
Can I make this sourdough pesto grilled cheese ahead of time?
You can assemble the sandwiches a few hours ahead and keep them wrapped in the fridge — just cook them fresh when you’re ready. Pre-cooked sandwiches reheat well in a pan or air fryer, though they’re always best fresh off the stove.
What’s the best pesto to use?
Honestly, a good quality store-bought pesto like Barilla is totally great here and saves time. If you enjoy making things from scratch, homemade basil pesto is even better and lets you control the flavor. Both work beautifully in this recipe.
Is this a good food to bring to a picnic?
Yes! It’s one of my favorite foods to bring to a picnic. Let the sandwiches cool completely, wrap them tightly in parchment paper, and pack them in a cooler bag. Slice them just before serving for the best texture.
Can I make this without bacon?
Absolutely — it’s still a fantastic sandwich without it. Roasted red peppers, sliced olives, or even a handful of fresh spinach are great alternatives if you want to keep it vegetarian. It’s one of those genuinely satisfying healthy grilled sandwiches even without the meat.
What other foods with pesto pair well with this sandwich?
Pesto is endlessly versatile! Serve this sandwich alongside a simple arugula salad dressed with lemon, a bowl of tomato soup, or even a light pasta. If you’re in a baking mood, these Lemon Blueberry Cake slices make a lovely dessert to follow up a pesto-themed lunch spread.
If you make this sourdough pesto grilled cheese, I really hope it ruins regular grilled cheese for you too — in the best possible way. Drop a comment below and let me know how it turned out, what variations you tried, or if you brought it to a picnic (I need to hear about it).
And if you loved it, please share it on Pinterest so more people can discover the magic of pesto in a grilled cheese. You’ll be doing the world a genuine favor.
