In a bowl, combine the milk and egg, and season with salt, pepper, garlic powder, and onion powder. Add the pork and let it marinate for about 15 minutes to help tenderize the meat.

Season the breadcrumbs with salt, pepper, garlic powder, and onion powder. Remove the pork from the marinade, let the excess liquid drip off, and coat each piece in the seasoned breadcrumbs.
Meanwhile, heat the vegetable oil in a skillet over medium heat. When hot, carefully add the breaded pork and cook for about 3 minutes per side, until golden brown. Transfer to paper towels to drain excess oil.

Slice the tomatoes and onion. Wash and drain the lettuce.
Slice the telera rolls in half, spread mayonnaise on both sides, and toast them on a hot griddle or skillet.