A sandwich with five parts and no place to hide — that’s a BLT. Thick-cut bacon, a tomato that’s actually ripe, sturdy sourdough, good lettuce. And until recently, the mayo was the one component just sitting in the middle, creamy and doing nothing. I fixed that with a jar of mayonnaise, a sprig of fresh rosemary, and a squeeze of lemon. Stir, and suddenly there’s a savory, herby brightness running through the whole sandwich.
I may never make a plain BLT again — and honestly, I’m a little annoyed at myself for waiting this long. Back when I worked the line, we’d punch out a hundred of these a day. None of them had this mayo. All of them should have.
Why this works
Fresh rosemary, garlic, and lemon give the mayo a savory, herbal lift that plain mayo just doesn’t have. It’s not about making something complicated — it’s about making the one ingredient in the sandwich that’s supposed to taste boring actually taste like something. Five minutes of stirring, and the whole sandwich changes.
Buy good stuff
This sandwich has five components, and not one of them can hide. Here’s the short list:
- Thick-cut bacon. The thin kind turns to lace. Thick-cut stays crispy without turning to rubber.
- A ripe, juicy summer tomato — heavy for its size, fragrant near the stem. A BLT is not the place for a sad, watery one.
- Bread that won’t collapse. Sourdough is my favorite here, but any sturdy sandwich loaf works.
- Good, crunchy lettuce. Romaine, butter lettuce, green leaf — whatever’s freshest at the store.
Then slather that mayo on generously. Both sides. All the way to the edges. That part’s not optional.
BLT Tips (learned the hard way, so you don’t have to)
I made this sandwich a handful of times before I got it right. A few things that actually matter:
- Salt the tomatoes. Lay the slices on a paper towel, sprinkle with flaky salt, and give them five minutes while you toast the bread. It pulls out a little water (good for sogginess) and seasons them all the way through (good for flavor). A small step that makes a real difference.
- Let the mayo sit. The garlic and rosemary need time to season the mayo. Fifteen minutes is the minimum, half an hour is noticeably better, and the next day is even better. If you’re prepping ahead, this is the one part of the sandwich that actually improves with time.
- Bake the bacon if you’re making more than a couple sandwiches. Sheet pan, 400°F (200°C), walk away. It crisps more evenly than the skillet, and your stovetop stays clean.
- Eat it immediately. This is not a make-ahead sandwich. Assemble, slice, eat. The bacon’s crispy and the toast is warm for about four minutes after that, and then it’s just a very good sandwich that’s slightly less good.
Make it your own
The classic bacon-lettuce-tomato combo is hard to beat, but there are plenty of fun ways to play:
- Sliced avocado makes a creamy BLAT — genuinely great with the rosemary mayo.
- Arugula instead of lettuce for a peppery version (my personal fave).
- A fried egg for extra protein.
- Thinly sliced red onion for crunch and a sharper bite.
- A little crushed red pepper, cayenne, or Calabrian chile paste stirred into the mayo if you like heat.
- Balsamic vinegar instead of lemon in the mayo for a deeper, slightly sweeter flavor.
- Sliced fresh mozzarella for a BLT-meets-caprese. Truly so good.
- Grill the bread with a little olive oil instead of toasting, for a smoky, extra-crisp version.
FAQ
Can I make the rosemary mayo ahead of time?
Definitely. It keeps in an airtight container in the fridge for about a week — and I think it’s better on day two than day one. It’s also great on burgers, roasted potatoes, and as a dip for anything fried.
Can I use dried rosemary instead of fresh?
Fresh is much better here. Dried rosemary is tougher and has a more concentrated, woodsy flavor that doesn’t blend into the mayo as naturally. In a pinch, use only a very small amount, and crush it finely between your fingers first.
How do I keep my BLT from getting soggy?
Toast the bread, spread mayo on both slices, briefly drain very juicy tomato slices on a paper towel, and assemble just before serving. I also put the lettuce directly against one side of the bread — it acts as a second barrier between the tomatoes and the toast.
BLT with Rosemary Mayo
Makes 4 sandwiches · 15 min prep + 20 min cook = 35 min total (the mayo takes 5 of those prep minutes; the rest is chopping and toasting)
Ingredients
For the rosemary mayo
- 1/2 cup mayonnaise (about 120 ml)
- 1 teaspoon finely chopped fresh rosemary
- 1 teaspoon lemon juice
- 1/2 teaspoon Dijon mustard
- 1 small garlic clove, pressed or finely minced
- Freshly-ground black pepper, to taste
For the BLTs
- 8 slices thick-cut bacon
- 8 slices sourdough, sandwich bread, or whatever sturdy bread you have
- 2 large ripe tomatoes, sliced
- 4 leaves romaine, butter lettuce, or green leaf lettuce
- Flaky sea salt and freshly-ground black pepper
Instructions
- Make the rosemary mayo. Stir together the mayonnaise, rosemary, lemon juice, Dijon, garlic, and a few twists of black pepper until combined. Taste and add more rosemary, lemon, or pepper if you want. This is the 5-minute part.
- Cook the bacon. Skillet over medium heat until crispy, or bake on a parchment-lined sheet pan at 400°F (200°C) for 15 to 20 minutes. Transfer to a paper towel-lined plate to drain.
- Toast the bread until golden and crisp.
- Season the tomatoes. Sprinkle the slices lightly with flaky sea salt and black pepper. With fresh summer tomatoes this makes a huge difference — it pulls out a little water and seasons them through.
- Assemble. Spread a generous layer of rosemary mayo on one side of each slice of toast, all the way to the edges. Layer with lettuce, bacon, and tomato slices.
- Serve. Close the sandwiches, slice in half, and eat while the bacon is still crispy and the toast is warm. Don’t overthink it.
Back when I worked the line, we had a rule: if a sandwich takes more than two hands to fix, it’s not a sandwich, it’s a project. This one’s two hands, one jar of mayo, and 35 minutes. It’s a sandwich.
Trade-It Tip
No fresh rosemary? A little dried rosemary works in a pinch — but use a small amount, and crush it between your fingers first so it distributes evenly instead of landing in one big woody chunk.
If it doesn’t fit a Tuesday night, it doesn’t get published.
— Grace