Chimichurri Filet Mignon Steak Sandwich
Cast iron-seared filet mignon topped with housemade chimichurri, caramelized onions, smoked pepperjack, and dijon aioli on toasted ciabatta. Steak finishes in a 400°F oven to medium-rare, then sliced thin and layered with fresh herb sauce for a restaurant-quality sandwich.
Ingredients
- filet mignon, seasoned
- 1 large white onion, diced
- olive oil
- sherry
- salt and pepper(optional)
- vegetable oil
- unsalted butter
- rosemary
- garlic cloves
- 1 ciabatta bread loaf, sliced lengthwise and toasted
- smoked pepperjack cheese, slicedsharp cheddar1:1mild alternative
4
- mayonnaise
- dijon mustard
- 1 shallot, roughly chopped
- 1 serrano pepper, seeds removed
- red wine vinegar
- salt
- red pepper flakes
- cilantro, roughly chopped
- parsley, roughly chopped
- dried oregano
- extra-virgin olive oilregular olive oil1:1budget option
4
Instructions
- 1
Heat a skillet on medium-low heat and sauté diced onion in olive oil, stirring frequently for 4-5 minutes, adding sherry halfway through.
- 2
Meanwhile, combine all chimichurri ingredients in a food processor and set aside.
- 3
In a medium bowl, mix dijon mustard and mayonnaise until combined and set aside.
- 4
Preheat oven to 400°F. Heat a cast iron skillet on high heat and add vegetable oil, butter, rosemary, and garlic.
- 5
Sauté garlic until brown and fragrant, about 30 seconds.
- 6
Add seasoned steak to pan and sear for 1-2 minutes per side.
- 7
Transfer skillet to oven and cook for 6-8 minutes until internal temperature reaches 135°F.
- 8
Rest steak at least 5 minutes, then slice thin across the grain.
- 9
Spread dijon aioli on toasted bread slices and layer with steak, cheese, caramelized onions, and chimichurri sauce.
- 10
Top with remaining bread slice and serve.
Tips
Slice steak across the grain for maximum tenderness in each bite.
Use a meat thermometer to ensure accurate doneness; 135°F yields medium-rare with a warm red center.
Toast ciabatta bread immediately before assembly to maintain crispness.
Good to Know
Chimichurri keeps refrigerated up to 3 days. Assembled sandwich best served immediately; steak slices can be refrigerated separately for up to 2 days.
Prepare chimichurri and dijon aioli up to 1 day ahead. Caramelize onions up to 2 days ahead and reheat gently. Sear and finish steak fresh for best results.
Serve immediately while bread is warm and cheese is melted. Cut in half for easier handling.
Common Mistakes
Overcook steak by leaving in oven beyond 8 minutes to avoid a steak that is gray throughout rather than rosy medium-rare.
Skip the rest period to avoid dense, tough meat that has not redistributed juices.
Slice steak with the grain instead of against it to avoid chewy pieces.
Substitutions
4