Save to Pins I was staring at a bag of wilting spinach one Saturday morning, determined not to waste it, when the idea hit me. What if I blended it into pesto and slathered it inside a grilled cheese? The kitchen smelled like garlic and toasted pine nuts within minutes, and by the time I pulled that first sandwich off the skillet, golden and oozing, I knew I'd stumbled onto something worth repeating. It's become my go-to whenever I want comfort with a little edge.
The first time I made this for friends, I panicked because I'd run out of basil and used only spinach. They didn't notice, they just kept reaching for seconds and asking what made the pesto taste so green and alive. I realized then that spinach doesn't just stretch the recipe, it makes it earthier and more interesting. Now I actually prefer it this way, with just a handful of basil to keep things honest.
Ingredients
- Fresh spinach leaves: Packed tight, they blend into a vibrant green base that's milder than all basil and sneaks in extra nutrition without anyone noticing.
- Fresh basil leaves: Just enough to bring that classic pesto aroma without overpowering the spinach, like a whisper of summer in every spoonful.
- Grated Parmesan cheese: This adds the salty, nutty backbone that makes pesto taste like pesto, so don't skip it or swap it for something bland.
- Toasted pine nuts: They turn creamy and rich when blended, giving the pesto body and a subtle sweetness that balances the garlic.
- Garlic clove: One large clove is plenty, it mellows as it blends but still gives you that unmistakable warmth.
- Extra virgin olive oil: This is what makes the pesto silky and pourable, so use something you'd happily dip bread into.
- Lemon juice: A tablespoon brightens everything and keeps the spinach from tasting too heavy or muddy.
- Sourdough or country bread: Sturdy enough to hold up to the pesto and butter without getting soggy, with a crust that crisps up beautifully.
- Unsalted butter: Softened so it spreads easily, it's what gives you that golden, crackling exterior.
- Mozzarella cheese: The stretchy, melty star that holds everything together and makes you want to pull the sandwich apart slowly.
- Sharp cheddar cheese: It adds a tangy punch that keeps the sandwich from being one note, cutting through the richness with personality.
Instructions
- Blend the Pesto:
- Toss the spinach, basil, Parmesan, pine nuts, garlic, salt, and pepper into your food processor and pulse until everything is finely chopped and starting to cling together. With the motor running, drizzle in the olive oil and lemon juice slowly, watching it transform into a smooth, glossy paste that smells like a garden after rain.
- Butter the Bread:
- Spread softened butter generously on one side of each slice, making sure to get all the way to the edges so every bite crisps up evenly. Lay them buttered side down on your counter, ready to build.
- Assemble the Sandwiches:
- Spread a tablespoon of that vibrant green pesto on the unbuttered side of two slices, then pile on half the mozzarella and cheddar on each. Top with the remaining slices, buttered side facing out, and press down gently so everything holds together.
- Grill Until Golden:
- Heat your skillet over medium heat and lay the sandwiches in carefully, listening for that first sizzle. Cook for three to four minutes per side, pressing down lightly with your spatula, until the bread turns deep golden and the cheese starts oozing out the sides.
- Rest and Serve:
- Let the sandwiches sit for a minute or two so the cheese sets just enough to hold its shape when you slice. Cut them in half and serve while they're still warm and the cheese is at its stretchiest.
Save to Pins There was a rainy Tuesday when I made this with a bowl of tomato soup on the side, and it felt like the kitchen wrapped itself around me like a blanket. My partner walked in, took one look, and said it smelled like a hug. That's when I realized this sandwich isn't just food, it's the kind of thing you make when you need to feel taken care of, even if you're the one doing the cooking.
How to Store Leftover Pesto
I always make extra pesto and keep it in a small jar in the fridge, topped with a thin layer of olive oil to keep it from browning. It lasts about a week and turns into an instant flavor boost for pasta, scrambled eggs, or even stirred into soup. Sometimes I freeze it in ice cube trays so I can pop out a cube whenever I need a quick hit of green goodness.
Choosing the Right Bread
Sourdough is my favorite because the tang plays nicely with the pesto and the crust gets impossibly crispy, but any sturdy bread works as long as it's not too soft or airy. I've used whole grain, rye, and even ciabatta, and they all bring something different to the table. The key is making sure the slices are thick enough to hold up to the butter and cheese without falling apart in the pan.
Serving Suggestions and Pairings
This sandwich begs to be dunked into a bowl of hot tomato soup, the acidity cutting through the richness in the best way. I've also served it alongside a simple arugula salad dressed with lemon and olive oil, which adds a peppery freshness that balances the gooey cheese. On lazy nights, I'll just eat it with a handful of chips and call it a win.
- Add a few slices of ripe tomato or roasted red pepper inside for extra moisture and sweetness.
- Try sprinkling a little grated Parmesan on the buttered side of the bread before grilling for an extra crispy, cheesy crust.
- If you want a little heat, stir a pinch of red pepper flakes into the pesto before spreading.
Save to Pins This sandwich has earned a permanent spot in my weekly rotation because it's proof that comfort food doesn't have to be boring. Once you taste that first bite, crispy and buttery on the outside with bright green pesto mingling with molten cheese, you'll understand why I keep coming back to it.
Frequently Asked Questions
- → Can I make the spinach pesto ahead of time?
Yes, prepare the pesto up to 3 days in advance and store it in an airtight container in the refrigerator. You can also freeze it for up to 2 months for longer storage.
- → What bread works best for this sandwich?
Sourdough and country bread are ideal for their sturdy texture and ability to hold up to buttering and grilling. Thick-cut bread prevents sogginess while ensuring even toasting and melting.
- → How do I prevent the cheese from leaking out?
Build the sandwich with cheese layered between the two bread slices and spread pesto on the inner surfaces. Press gently while cooking and maintain medium heat to allow cheese to melt gradually without escaping.
- → What are good substitutes for pine nuts?
Walnuts, almonds, or roasted sunflower seeds work excellently as pine nut alternatives. They provide similar richness and texture while being more budget-friendly and allergen-friendly.
- → Can I add vegetables to this sandwich?
Absolutely. Sliced tomato, roasted red peppers, or arugula complement the pesto beautifully. Layer them with the cheese for added flavor, texture, and nutrition.
- → What temperature should my skillet be?
Use medium heat to allow the bread to crisp while the cheese melts completely. Medium-high heat may brown the exterior too quickly before the cheese melts through.