Pepper Jack is Monterey Jack with chile or other peppers mixed into the curd. The base cheese is still the mild California Jack.
The heat is in the peppers, not in a long aging. Pepper Jack melts the same way young Jack does. It has no ancient homeland and no protected name.
History
Pepper Jack is a twentieth-century American cheese. Once young Jack was a national melting cheese, dairies began to stir peppers into the curd to give a mild cheese a second job. The idea needed no old recipe. A quiet cheese plus chile was enough.
There is no village of Pepper Jack, and there is no appellation to protect. Makers use jalapeño, and sometimes bell pepper, cayenne, or other chiles. The mix is a recipe, not a place. That is why two packages with the same name can differ in heat. Read the pepper, not a romantic origin.
How it is made
The cheese is young Jack up to the moment the curd is salted and pressed. Peppers are mixed through the curd so the heat is in every slice, not dusted on the outside. The block is then pressed and sold fresh, with little or no rind, like plain Jack.
Nothing in the make concentrates the spice. Age is not part of the style. A Pepper Jack that has dried out in the back of a refrigerator is not a better Pepper Jack. It is a melting cheese that was forgotten. The peppers also make the block a little more perishable than plain Jack, because they break up the paste.
Taste
The paste tastes like young Jack: milky, salty, and a little sweet. The peppers add green, red, or smoky notes, and a heat that can be gentle or sharp depending on the chile. The cheese itself does not become sharp the way an old cheddar does.
A good piece smells of milk and fresh pepper. A fermented, sour, or muddy smell means the peppers or the cheese have turned. Heat should taste clean. If the only sensation is a bitter burn, the chile was poor or the cheese is stale.
In the kitchen
Use Pepper Jack anywhere young Jack would melt, when the dish also wants heat. Quesadillas, burgers, omelets, nachos, and stuffed peppers are the usual places. It melts into a stretch and leaves flecks of chile behind. It is a shortcut. It saves you from shredding Jack and chopping a pepper.
Do not treat it as a seasoning cheese for a whole pot. A little goes into a sandwich. A lot can make a sauce greasy and hot without tasting of cheese. It is a poor grating cheese, and it is a poor choice on a board next to delicate foods. Pair it with beans, corn, tomatoes, or beef. For a cheese course, choose something that was aged on purpose.
Around the world
Pepper Jack is eaten in the United States, in restaurants and at home, wherever Jack and Mexican-American food share a menu. Stadium nachos, chain burgers, and weeknight quesadillas made it ordinary. It is not a regional specialty with a season or a feast day.
Other countries flavor melting cheeses with chile, but they do not need this name. A peppered cheddar is a different cheese, sharper in the paste and often hotter at the rind. A Mexican cheese with chile is a different tradition again. When a recipe from an American kitchen says Pepper Jack, it wants a mild melting block with peppers in it, not a wheel of aged cheese.