"Nigella stars as a nutty allium-flavored pop of texture and flavor in this take on the classic. For a heavier hint of sweet heat, add paprika and black pepper. A grilled cheese is a grilled cheese, which means you can use any cheese you have on hand in this sandwich: mozzarella, Parm, Gruyère."
In a medium skillet over medium heat, toast nigella seeds, stirring occasionally, until fragrant, about 1 minute. Transfer to a bowl.
Return skillet to medium heat. Spread butter evenly over one side of each slice of bread and place bread buttered side up. Let bread toast until hot, 1 minute, then flip. Immediately place Gouda and nigella on one slice, and cheddar, paprika and pepper on the other. Sprinkle pecorino over both slices.
Reduce heat to low and continue cooking until bread is golden and cheese has melted. Add basil, then close the sandwich and transfer to a plate. Let cool slightly before serving!