In large bowl gently combine shredded cheeses.
Lay out sourdough breads slices, brush both sides with oil.
Place 12 bread slices "bottoms" on sheet pan, oiled side down.
Place 2 slices of Pepper Jack cheese on each side of bottom bread.
Place 4 slices of jalapeño on top of each cheese portion.
Using #20 scoop, carefully place shredded cheese mixture on top of jalapeños. Divide any remaining cheese among the portions.
Place top bread layer on sandwich, oiled side up. Bake in preheated 400°F oven for 12 to 15 minutes.
Hold warm until service.
CCP: Maintain hot food at 135°F or above