Save My skillet was too hot the first time I made this, and I ended up with charred bread and cold cheese in the middle. I learned that day that patience matters, especially when you're trying to marry something as bright as spinach pesto with something as comforting as melted cheese. The second attempt was slower, quieter, and absolutely worth the wait. Now this sandwich shows up on my stove every time I need something quick but refuse to settle for boring.
I made this for my sister after she claimed she hated pesto, and she finished both halves before I could take a photo. She still swears it was the butter and the crispy edges that won her over, but I saw her scraping extra pesto from the jar when she thought I wasnt looking. Sometimes the best way to change someones mind is to hide the green stuff inside something golden and melted.
Ingredients
- Fresh spinach leaves: Use baby spinach if you can, it blends smoother and tastes milder than the big tough leaves, and you wont need to remove stems.
- Fresh basil leaves: Basil brings that classic pesto sweetness and rounds out the mineral edge of spinach, so dont skip it even if spinach is the star.
- Grated Parmesan cheese: The salty, nutty backbone of any pesto, and it helps the sauce cling to the bread instead of sliding off.
- Toasted pine nuts: These add richness and a buttery texture, but walnuts work just as well and cost a lot less.
- Large garlic clove: One clove is plenty, raw garlic can take over fast, and you want it to hum in the background, not shout.
- Extra virgin olive oil: This is what makes the pesto silky and spreadable, so use something you would actually want to taste.
- Salt and black pepper: Season as you blend, pesto needs more salt than you think to bring all the flavors forward.
- Lemon juice: Just a tablespoon brightens everything and keeps the pesto from tasting flat or too heavy.
- Sourdough or country bread: A sturdy bread with some chew holds up to the pesto and butter without turning soggy.
- Unsalted butter: Softened butter spreads easily and crisps up beautifully, giving you that golden crust everyone fights over.
- Mozzarella cheese: The melt champion, it gives you those Instagram worthy cheese pulls.
- Sharp cheddar cheese: Adds a tangy punch that keeps the sandwich from being too mild or one note.
Instructions
- Blend the pesto:
- Toss spinach, basil, Parmesan, pine nuts, garlic, salt, and pepper into your food processor and pulse until everything is finely chopped and starting to come together. With the motor running, pour in the olive oil and lemon juice in a slow, steady stream until you have a smooth, spreadable paste that clings to a spoon.
- Butter the bread:
- Spread softened butter generously on one side of each slice of bread, all the way to the edges. Lay them buttered side down on your counter so youre looking at the bare side.
- Assemble the sandwiches:
- Spread 1 tablespoon of spinach pesto on the unbuttered side of two slices, then pile on half the mozzarella and cheddar. Top with the remaining bread slices, buttered side facing out, and press gently so everything sticks together.
- Grill low and slow:
- Heat a large skillet over medium heat and let it warm up for a full minute before you add the sandwiches. Cook for 3 to 4 minutes on the first side without moving them, pressing down gently with a spatula, until the bread turns deep golden brown and the cheese starts to soften.
- Flip and finish:
- Carefully flip each sandwich and cook the second side for another 3 to 4 minutes, pressing again, until both sides are equally crispy and the cheese is fully melted. Let them rest for a minute before slicing so the cheese doesnt all run out onto your plate.
Save The first time I served this at a casual lunch, my friend asked if I had ordered it from somewhere. I told her it was just grilled cheese with pesto, and she looked at me like I had been holding out on her for years. Now she texts me every time she makes it, usually with a photo and way too many emojis.
Making the Pesto Ahead
You can make a big batch of spinach pesto and store it in the fridge for up to a week, just press a piece of plastic wrap directly on the surface to keep it from browning. It also freezes beautifully in ice cube trays, so you can pop out a tablespoon whenever you need it for pasta, sandwiches, or scrambled eggs. I always make extra because it disappears faster than I expect.
Choosing Your Cheese
Mozzarella is non negotiable for melt and stretch, but the second cheese is where you can play around. Sharp cheddar brings tang, Gruyere adds nuttiness, and fontina gives you a creamy, mild sweetness. I have even used crumbled goat cheese when I wanted something a little funky and it worked. Just make sure one of your cheeses melts well, or youll end up with a sad, grainy filling.
Serving Suggestions
This sandwich is perfect on its own, but it loves being dipped into a bowl of tomato soup or served next to a simple arugula salad with lemon vinaigrette. If youre feeling fancy, add a few slices of roasted red pepper or sun dried tomatoes inside before you grill it. I have also tucked in some fresh mozzarella slices for extra creaminess, and no one complained.
- Serve with a handful of kettle cooked chips if you want that salty crunch contrast.
- Pair it with a cold glass of white wine or sparkling water with lemon for an easy lunch that feels a little special.
- Leftovers reheat surprisingly well in a skillet over low heat, just cover the pan so the cheese softens again without burning the bread.
Save This sandwich has ruined regular grilled cheese for me in the best way possible. Now I keep a jar of spinach pesto in the fridge just in case the craving hits, because once you taste that first bite of garlicky green against sharp, melted cheese, theres no going back.
Recipe Questions & Answers
- → Can I make the spinach pesto ahead of time?
Yes, the spinach pesto can be prepared up to 2 days in advance. Store it in an airtight container in the refrigerator. You can also freeze it for up to 3 months in ice cube trays for portion control.
- → What bread works best for this sandwich?
Sourdough and country bread are excellent choices for their sturdy structure and mild tang. Brioche, ciabatta, or thick-cut white bread also work well. Avoid thin-sliced bread as it may tear under the weight of melted cheese.
- → How do I prevent the cheese from leaking out?
Layer the cheese evenly between the bread slices and don't overstuff. Keep the heat at medium to allow the cheese to melt gradually without the bread browning too quickly. Pressing gently while cooking helps distribute heat evenly.
- → Can I substitute the pine nuts in the pesto?
Absolutely. Walnuts, almonds, or roasted sunflower seeds are great alternatives. For those with nut allergies, sunflower seeds or pumpkin seeds provide a similar creamy texture and nutty flavor.
- → What are some good side dishes to serve with this?
A simple green salad with vinaigrette, tomato soup, minestrone, or potato chips pair wonderfully. You can also add fresh fruit like grapes or berries for a balanced meal.
- → Can I make this gluten-free?
Yes, simply use gluten-free bread in place of regular bread. All other ingredients are naturally gluten-free. Ensure your gluten-free bread is sturdy enough to handle buttering and grilling without falling apart.