Roast Beef Sandwich with Roasted Red Pepper Aioli
This roast beef sandwich layers thinly sliced leftover prime rib with melted Gruyère and a bright, garlicky roasted red pepper aioli spiked with capers—elevated deli comfort on toasted French bread.
This roast beef sandwich layers thinly sliced leftover prime rib with melted Gruyère and a bright, garlicky roasted red pepper aioli spiked with capers—elevated deli comfort on toasted French bread.
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Char the red bell pepper directly over a gas stove flame until the skin is blackened all over.
Place the hot pepper in a bowl and cover to let it steam for about 10 minutes. Then, peel off the charred skin and roughly chop the pepper.
To a food processor, add garlic, egg yolks, and lemon juice. Blend until combined.
With the food processor running, slowly stream in the olive oil to create an emulsion for the aioli.
Add the chopped roasted red pepper, fresh basil, capers, and a pinch of salt to the food processor. Blend until smooth.
Slice the French bread loaf in half lengthwise and toast it cut-side down on a hot pan or griddle.
Arrange the sliced tomatoes on a plate and season with salt, black pepper, and a drizzle of vinaigrette.
Gently reheat the thinly sliced prime rib in a pan over medium heat until just warmed through.
To assemble the sandwich, spread a generous layer of the roasted red pepper aioli on the toasted bread.
Pile the warmed prime rib onto the bottom half of the bread.
Top the meat with slices of Gruyère cheese and melt using a kitchen torch or by placing it under a broiler.
Layer the seasoned tomatoes, arugula, and sliced pepperoncini over the melted cheese.
Finish with a generous amount of grated Parmesan cheese.
Place the top half of the bread on, slice the sandwich in half, and serve immediately.
Assemble just before serving for best texture. Store aioli refrigerated up to 2 days; reheat leftover roast beef gently in a skillet or oven at 325°F until warm through.
Yes. Prepare the roasted red pepper aioli up to 2 days ahead and refrigerate in an airtight container. Stir before serving.
Thinly sliced deli roast beef, ribeye, or sirloin work well. For best texture, slice against the grain when meat is slightly chilled.
Yes. Swiss, aged cheddar, or provolone are good alternatives; avoid softer cheeses that won't melt properly on warm meat.
It should be thick and creamy, like mayo. If it breaks, start with a fresh egg yolk in a clean bowl and slowly whisk in the broken aioli until it emulsifies.
Yes. They add briny, salty notes—skip them for a cleaner roasted pepper flavor, or replace with chopped cornichons.
