In a shallow dish, combine the beaten eggs and milk. Whisk in salt and pepper. Set aside.

Heat the oil in a frying pan over medium-high heat.

On 8 of the bread triangles, layer a slice of tomato, a slice of mozzarella cheese, and 2 pepperoni slices.

Cover the filled bread triangles with the remaining 8 slices of bread to form sandwiches. Press down gently and seal the edges.

Dip each sandwich into the egg mixture, ensuring both sides are coated. Let soak for about 20 seconds per side.

Carefully place the egg-coated sandwiches into the hot oil, one at a time. Fry for about 2 minutes on the first side.

Flip the sandwiches carefully with tongs and cook for another 30 seconds to 1 minute, until golden brown and the cheese is melted.

Remove the sandwiches with a slotted spoon and drain well on paper towels.

Serve immediately.