Blueberry Grilled Cheese with White Cheddar and Homemade Jam
Crisp sourdough gives way to melted cheese and a warm blueberry filling with just enough lemon to keep it from tasting overly sweet. This blueberry grilled cheese is my take on the familiar sandwich, built with sharp white cheddar, mild mozzarella, and a simple lemon-thyme jam.
It takes a little longer than spreading store-bought preserves on bread, though the homemade filling is worth the extra pan. You get a better balance of fruit, acidity, salt, and rich melted cheese in every bite.
How to Make Blueberry Grilled Cheese with White Cheddar
Simmering the Blueberry Lemon-Thyme Jam
Add 1 pint of fresh blueberries, ¼ cup granulated sugar, the juice of 1 lemon, and the tied lemon-thyme sprigs to a 2-quart saucepan. Bring the mixture to a boil over medium-high heat, then lower it to medium-low and let it simmer for about 10 minutes.
The berries will begin to burst and release plenty of liquid. At that point, reduce the heat to low and continue simmering for another 10 minutes. Stir often, especially as the mixture thickens. Fruit and sugar can catch on the bottom quickly once most of the water has evaporated.
Look for a loose jam rather than a stiff preserve. Drag a spoon across the bottom of the pan; the line should stay visible for a moment before the mixture slowly flows back together. It will thicken more as it cools.
Remove the bundle of lemon thyme and let the jam rest for 10 minutes. That cooling time matters. Jam that is still bubbling hot can soak into the bread and make the sandwich harder to turn in the skillet.
Building the Sweet and Savory Sandwiches
Lay out four of the ¼-inch-thick sourdough slices and spread the cooled blueberry jam across them. Keep a narrow border around the edges. Filling pushed all the way to the crust tends to escape once the sandwich is pressed and heated.
Divide 4 ounces of shredded white cheddar and 4 ounces of shredded mozzarella among the four slices. I prefer shredding both cheeses from blocks because the strands melt more smoothly than many packaged shredded cheeses.
The two cheeses do different jobs here. White cheddar brings the salty, sharp flavor needed to stand up to the sweet berries. Mozzarella softens that sharpness and gives the center its stretchy, creamy texture.
Place the remaining bread slices on top and press them down lightly. Don’t flatten them. A gentle press is enough to hold the layers together while leaving room for the cheese to melt.
Toasting the Bread Without Burning It
Heat a 12-inch cast-iron skillet over medium heat and add 2 tablespoons of butter. Once the butter has melted and stopped foaming heavily, place two sandwiches in the skillet.
Cover the pan with a lid and cook for 2–3 minutes. The trapped warmth helps the cheese melt before the bread becomes too dark. Check the underside at the two-minute mark. You’re looking for an even golden surface with crisp edges, not a few dark patches surrounded by pale bread.
Flip the sandwiches carefully and cook the second side for another 2–3 minutes, keeping the skillet covered. Lower the heat if the bread is browning faster than the cheese is melting. Cast iron holds heat well, so the second batch may need a slightly lower setting.
Transfer the cooked sandwiches to a cutting board. Add the remaining 2 tablespoons of butter and repeat with the other two sandwiches. Let each one rest for a minute before cutting. This gives the melted filling a chance to settle instead of running straight onto the board.
Finish with a small pinch of flaky sea salt and a few fresh lemon-thyme leaves. The salt sharpens the cheddar and keeps the fruit filling from dominating the sandwich.
A Grilled Cheese Worth Making During Blueberry Season
This sandwich works because no single part takes over. The blueberry jam stays bright from the lemon, the cheddar adds a savory edge, and the mozzarella melts everything together inside crisp sourdough.
Serve it warm, while the cheese still pulls and the bread has its skillet-fried crunch. It’s familiar enough for lunch and just different enough to remember.
Blueberry White Cheddar Grilled Cheese
Ingredients
Equipment
Method
- Combine the blueberries, granulated sugar, lemon juice, and tied lemon thyme sprigs in a 2-quart saucepan over medium-high heat.
- Bring the blueberry mixture to a boil, then reduce the heat to medium-low and simmer for about 10 minutes.
- Reduce the heat to low and continue simmering for another 10 minutes, stirring often, until the berries have broken down and the mixture has thickened into a loose jam.
- Remove and discard the lemon thyme bundle, then let the blueberry jam cool for 10 minutes so it thickens and does not soak into the bread.
- Lay four sourdough slices on a work surface and spread the cooled blueberry jam over each slice, leaving a narrow border around the edges.
- Divide the shredded white cheddar and mozzarella evenly over the jam, then top with the remaining four bread slices and press gently to close.
- Heat a 12-inch cast-iron skillet over medium heat and melt 2 tablespoons of the butter.
- Place two sandwiches in the skillet, cover with a lid, and cook for 2 to 3 minutes until the undersides are evenly golden.
- Flip the sandwiches carefully, cover again, and cook for another 2 to 3 minutes until the second sides are golden and the cheese is fully melted, lowering the heat if the bread browns too quickly.
- Transfer the cooked sandwiches to a cutting board, melt the remaining 2 tablespoons of butter in the skillet, and repeat with the final two sandwiches.
- Let the sandwiches rest for 1 minute, cut them in half, and finish with flaky sea salt and fresh lemon thyme leaves before serving warm.
Notes
- Keep the blueberry mixture at a gentle simmer and stir it often during the final 10 minutes so the sugar does not catch on the bottom of the saucepan.
- The jam should look slightly loose while warm because it will continue to thicken as it cools.
- Shredding the cheeses from blocks helps them melt more smoothly than many packaged pre-shredded cheeses.
- Covering the skillet traps enough heat to melt the cheese before the sourdough becomes too dark.
- Lower the heat for the second batch if the cast-iron skillet has become very hot.
