Slice the jalapeños thinly, removing the seeds if you prefer a milder heat. Place the jalapeños slices on a baking sheet and brush with olive oil. Place under the broiler for 2-4 minutes or until the slices start to get a little blackened and have softened.
Take two slices of bread and spread a thin layer of butter on one side of each slice. Place the buttered side down on a clean surface.
Spread the cream cheese evenly onto one side of the sandwich. Add a layer of jalapeños. Divide the shredded cheese and the Pepper Jack cheese evenly between the two slices, spreading it out to cover the entire surface.
Place the remaining slices of bread on top of the cheese, ensuring that the buttered side is facing up.
In a large skillet or griddle, heat the olive oil over medium heat. Carefully transfer the assembled sandwiches to the skillet and cook until the bottom is golden brown and crispy, about 3-4 minutes. Using a spatula, carefully flip the sandwiches and continue cooking until the other side is golden brown and the cheese is melted, about 3-4 minutes more.
Once both sides are crispy and the cheese is gooey, remove the sandwiches from the skillet and transfer them to a cutting board. Let them cool for a minute or two before slicing them in half. Serve immediately with a side of creamy tomato soup or your favorite dipping sauce.