The idea for this recipe began with a question: How many tomatoes can I cram into a grilled cheese without it turning to mush? The answer is a sandwich slathered on one side with tomato butter, and filled with jammy, slow-cooked tomatoes to complement a blend of gruyere and sharp cheddar cheese.
Yes, this sandwich takes a bit of patience to make, but you wait all year for tomato season, so what’s another few hours?
Any leftover cooked tomatoes or butter can be used for your next sandwich, or on toast for breakfast. —Leslie Engel
butter, at room temperature
tomato juices/oil left over from slow-cooked tomatoes
sourdough bread, thinly sliced (about 1/2 inch thick)
For the slow-cooked tomatoes:
Place tomatoes in a medium saucepan and drizzle with olive oil. Add salt and gently stir with a large spoon to ensure all the tomatoes are covered with olive oil and salt. Place on stovetop and turn on heat between low and medium-low. Allow tomatoes to cook for up to 4 hours, stirring occasionally. Tomatoes will burst and reduce by about half as they cook. Remove tomatoes from heat and transfer them, along with any excess juices and oil in the pan, to a small bowl.
For the tomato butter:
In a small bowl, combine butter, one tablespoon of the slow-cooked tomatoes and a teaspoon of the leftover tomato juices and oil. Use the back of a fork to burst the tomatoes if necessary. Once combined, return to the refrigerator to harden slightly.
Combine grated cheeses in a small bowl.
Heat a skillet over medium heat. Generously butter two slices of bread on one side with tomato butter. Place one slice of bread, butter side down, in the skillet. Mound about ½ cup of cheese (or as much that will fit and your conscience can handle) onto bread in pan.
Using a spoon, carefully press as many cooked tomatoes as possible on top of the cheese. Add another ¼ to ½ cup of cheese on top of the tomatoes. Place second slice of bread on top, with the butter side facing up. Cook on one side for two to three minutes, pressing down on sandwich with a spatula. Carefully flip over and cook on the other side for another two to three minutes. Bread will be toasted to a golden brown and cheese will be melted.
Remove from heat. Place sandwich on a plate, cut in half and discover that the wait was worth it.