Heat olive oil in a large skillet over medium heat. Add onion and pepper and saute for 5-10 minutes, stirring often, until softened. Add garlic and cook for 1 minute. Add roast beef and Worcestershire sauce and stir to combine. Season to taste with salt and pepper. Remove from heat and let cool.
Add vegetable oil to a large deep saute pan and fill to 1 1/2-2” deep. Heat over medium-high heat or until 350 degrees if using a deep fry thermometer.
Assemble Eggrolls: Working one at a time, place an egg roll wrapper on a flat surface with a corner pointing towards you. Place ~3 TB shredded or grated imported Provolone on top, then one scoop of roast beef mixture, top with an additional 2 TB shredded or grated imported Provolone. Roll wrapper around filling rolling away from you, then fold in the sides. Continue rolling to completely enclose filling and seal the opposite corner with a dab of water. Repeat with all 8 egg roll wrappers and place on a small cookie sheet.
Working in batches based on your pan size to avoid crowding, pan or deep fry eggrolls for 2-3 minutes per side or until crispy and evenly browned. Place on a paper towel lined plate to drain while you finish frying the remaining eggrolls. Cut in half crosswise and serve with warm marinara sauce for dipping.