Spinach Pesto Grilled Cheese

I threw this together on a Tuesday afternoon when I had a bag of spinach threatening to wilt and half a block of cheese in the fridge. The pesto came together in minutes, and suddenly my plain grilled cheese idea became something I actually wanted to photograph. The kitchen smelled like garlic and toasted bread, and I remember thinking this might be too fancy for lunch alone, but I made it anyway. It was gone in minutes, and I've been making it ever since.

I made this for my neighbor once after she helped me carry groceries up three flights of stairs. She took one bite and asked if I was secretly a chef, which made me laugh because I had literally just learned you could put pesto inside a sandwich. We sat on my tiny balcony and ate them warm, and she told me it tasted like something from a cafe. That compliment stuck with me longer than it probably should have.

Ingredients

• Fresh spinach leaves: Packed spinach gives the pesto a mild, earthy flavor and a gorgeous green color without overpowering the garlic and cheese.
• Fresh basil leaves: Basil adds that classic pesto aroma and a sweet, peppery note that balances the spinach beautifully.
• Grated Parmesan cheese: This brings salty, nutty depth to the pesto and helps it cling to the bread and melt into the other cheeses.
• Toasted pine nuts: Pine nuts add buttery richness and a subtle crunch, though walnuts work just as well if that is what you have.
• Garlic clove: One large clove is enough to make the pesto punchy without burning your tongue, and it mellows as it sits.
• Extra virgin olive oil: This is what makes the pesto smooth and spreadable, and it carries all the flavors together into a silky paste.
• Lemon juice: A tablespoon brightens everything and keeps the pesto from tasting too heavy or flat.
• Sourdough or country bread: Thick slices with a sturdy crust hold up to the butter and pesto and crisp up like a dream.
• Unsalted butter: Softened butter spreads easily and creates that golden, crispy exterior everyone craves in a grilled cheese.
• Mozzarella cheese: Mozzarella melts into creamy, stretchy strands that make every bite satisfying and gooey.
• Sharp cheddar cheese: Cheddar adds a tangy, bold flavor that keeps the sandwich from being too mild or one note.

Instructions

Make 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 come together. With the motor running, drizzle in the olive oil and lemon juice until the mixture turns into a smooth, vibrant green paste that smells like summer.

Butter the bread:

Spread softened butter on one side of each slice of bread, making sure to go all the way to the edges so every bit crisps up evenly. Lay them buttered side down on your counter or cutting board.

Assemble the sandwiches:

Spread a tablespoon of that bright green pesto on the unbuttered side of two slices, then pile on the mozzarella and cheddar in an even layer. Top with the remaining bread slices, buttered side facing out, and press gently to help everything stick together.

Grill until golden:

Heat your skillet over medium heat and lay the sandwiches in carefully, cooking for about 3 to 4 minutes on each side. Press down lightly with your spatula and watch as the bread turns golden brown and the cheese starts to ooze out the sides.

Rest and serve:

Let the sandwiches sit for a minute or two before slicing so the cheese sets just a little and does not all slide out. Cut them in half and serve while they are still warm and melty.

Pinterest

One evening I served this with tomato soup, and my friend dipped the sandwich right into the bowl without asking. I thought it was weird at first, but then I tried it and realized she was onto something. Now I cannot eat this without a side of something warm to dunk it into, and it has become one of those unspoken rules in my kitchen.

Storing and Using Leftover Pesto

The pesto recipe makes more than you need for two sandwiches, which is actually the best part. I keep the extra in a small jar in the fridge, and it stays fresh for about a week if you press plastic wrap directly onto the surface or drizzle a thin layer of olive oil on top to keep it from browning. I have stirred it into scrambled eggs, tossed it with warm pasta, and spread it on crackers with a little goat cheese when I needed a quick snack that felt fancy.

Choosing Your Cheese

Mozzarella and cheddar are my go to because one melts beautifully and the other brings flavor, but this sandwich is forgiving. I have used Gruyere when I wanted something nutty, fontina when I wanted it extra creamy, and even a little crumbled feta mixed in when I was feeling adventurous. The key is to use at least one cheese that melts well and one that has enough personality to stand up to the pesto.

Serving Suggestions

This sandwich does not need much to feel like a full meal, but I love pairing it with a handful of arugula dressed in lemon and olive oil, or a bowl of tomato soup that is just acidic enough to cut through the richness. Sometimes I add a handful of roasted red peppers inside the sandwich for sweetness, or a few slices of ripe tomato when they are in season and too good to skip.

• Serve with a crisp green salad tossed in a light vinaigrette to balance the richness of the cheese.
• Pair with tomato soup, roasted red pepper soup, or a simple broth based vegetable soup for dipping.
• Add sliced avocado, sun dried tomatoes, or caramelized onions inside the sandwich for extra layers of flavor.

Pinterest

This sandwich has become my answer to lazy weekends and quick dinners when I want something that feels special without much effort. I hope it shows up in your kitchen the same way it did in mine, unplanned and perfect.

Recipe FAQs

→ Can I make the spinach pesto ahead of time?

Yes, prepare the pesto up to 2 days in advance and store it in an airtight container in the refrigerator. You can also freeze it for up to 3 months. This makes meal prep convenient.

→ What's the best bread choice for this sandwich?

Sourdough and country bread work excellently due to their sturdy structure and ability to toast evenly. Brioche or thick-cut white bread are good alternatives if sourdough isn't available.

→ How do I prevent the cheese from leaking out?

Ensure your bread slices are thick enough and apply butter to the outer sides only. Cook on medium heat rather than high to allow the cheese time to melt without burning the bread.

→ Can I substitute the pine nuts?

Absolutely. Walnuts, almonds, or roasted sunflower seeds work great as substitutes. For a nut-free version, use sunflower seeds for a similar texture and nutritional profile.

→ What other ingredients can enhance this sandwich?

Try adding sliced tomatoes, roasted red peppers, caramelized onions, or thin slices of prosciutto. A touch of balsamic vinegar or honey can also add interesting depth to the flavor profile.

→ Is this suitable for a gluten-free diet?

Yes, simply use high-quality gluten-free bread and verify that all other ingredients meet your dietary requirements. The spinach pesto itself is naturally gluten-free.