Heat the oil in a large skillet over medium-high heat. Add the onion and bell pepper and cook for 5 to 6 minutes, stirring often, until softened and lightly browned at the edges.

Push the vegetables to one side, add the beef, and cook 2 to 3 minutes, until just cooked through; season with salt and pepper and stir everything together.

Remove from the heat and let cool for 10 minutes. Scatter the torn provolone over the warm, not hot, mixture so it begins to soften without fully melting.

Lay a wrapper in a diamond shape and spoon about 1/3 cup of the beef mixture onto the lower third.

Fold the bottom point over the filling, fold in both sides, and roll tightly, sealing the final corner with egg wash.

Repeat with the remaining wrappers, keeping unused ones covered with a damp paper towel.

Air fry at 380°F: arrange seam side down with space between rolls, spray with oil, and cook 8 minutes. Flip and cook 5 minutes more, until the wrapper is deep golden and sounds hollow when tapped.

Or bake at 425°F on a parchment-lined sheet for 16 to 18 minutes, flipping once, until crisp and blistered.

Whisk the mayonnaise, horseradish, lemon juice and garlic powder together in a small bowl.

Let the egg rolls rest 3 minutes; the melted provolone inside stays molten well past the point the wrapper has cooled. Serve with the horseradish dip.