In a large skillet over medium heat, melt 4 Tablespoons salted butter. Add 3 cups small-diced onion, 2 teaspoons sugar and 1/2 teaspoon black pepper to the skillet and stir to combine. Continue cooking, frequently stirring, until the onions turn a golden brown color, 18-20 minutes. Drain excess oil.
In a small bowl, mix together 1 Tablespoon water and 1 Tablespoon all-purpose flour, this will make a “glue” to help seal the egg rolls.
On a clean work surface, place one of the 12 egg roll wrappers with one of the corners facing you. Add 2 slices of the 20 slices deli sliced roast beef to the bottom corner of the wrapper.
Add some of the 1 1/2 cups shredded provolone cheese (about 2 Tablespoons), on top of the roast beef. Place 1 ½ Tablespoons of the caramelized onions on top.
Take the corner and fold it up over the filling. Dip your finger into the flour mixture and run it along the exposed edges of the wrapper.
Tuck both edges of the wrapper over the filling. continue to roll until you make a little log tightly. Make sure all the edges are sealed.
Place on a sheet tray while you continue rolling the rest of the egg rolls.
Heat a deep fryer or dutch oven (or heavy bottom skillet with deep sides) with 4 inches of oil to 350°F.
Very carefully place a couple of the egg rolls into the hot oil and fry until golden brown, 5-6 minutes. Make sure to flip them often, so they brown evenly.
Place the egg rolls onto a paper towel-lined plate to absorb any excess oil. Then immediately place it onto a wire rack over a sheet tray.
Repeat with the remaining egg rolls.
While your egg rolls are frying, combine the 1 ounce packet au jus gravy mix with 3 cups cold water in a sauce pan and prepare per the directions on the back of the package.
Once the egg rolls are ready, serve with the au jus for dipping.
Notes
If you don't want to deep fry these, you can make them in the Air Fryer or oven, see the FAQ section for more info on that.
These would also be amazing dipped in steak sauce, yum!
Other cheeses that would work, white cheddar, swiss, Gruyere, and mozzarella.
You can also use leftover roast beef from dinner if you have any on hand.
We place the egg rolls on a wire rack over a sheet tray so they will not steam and become soggy. You can keep them in a warm oven while frying the remaining egg rolls if desired.
I like to use peanut oil when frying. It is a cleaner oil and doesn’t stink up the house as much.
These are best eaten after frying but if you have any leftovers, they will keep in the fridge for up to 3 days. To reheat, place them back into a deep fryer or you can bake them until warmed through.