Steak And Boursin Recipe
seared strip steak • Boursin • caramelized onion • balsamic reduction • baguette
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Ingredients
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Steak & finishing
Caramelized onions
Boursin spread
Balsamic reduction
Bread & assembly
Method
Balsamic reduction
Reduce
Combine 1/2 cup balsamic vinegar and 1 tsp sugar (or honey) in a small saucepan. Bring to a gentle boil over medium heat, then reduce to a simmer. Cook, stirring occasionally, until mixture thickens and coats the back of a spoon, about 8–12 minutes. Remove from heat and let cool — it will thicken more as it cools. Reserve for assembly.
Caramelized onions
Cook onions
Heat 1 tbsp olive oil and 1 tbsp butter in a medium skillet over medium-low heat. Add 1 cup thinly sliced yellow onion, 1/4 tsp kosher salt, and 1/4 tsp sugar. Cook slowly, stirring every few minutes, until onions are deeply golden and soft, about 20–25 minutes. If they begin to brown too quickly, reduce heat. In the last 2 minutes, add 1 tsp balsamic vinegar, stir to deglaze and concentrate flavor. Transfer onions to a bowl and keep warm.
Boursin spread
Prepare spread
In a small bowl, combine 3 oz Boursin cheese with 1 tbsp cream cheese (optional) until smooth and spreadable. Taste and add 1/4 tsp freshly ground black pepper if desired. Keep at room temperature until assembly so it remains soft.
Steak & finishing
Bring steak to room temperature
Pat 1 strip steak dry with paper towels. Season both sides evenly with 1 tsp kosher salt and 1/2 tsp freshly ground black pepper. Let sit at room temperature for 20–30 minutes while preparing other components.
Sear steak
Heat a heavy skillet (cast iron preferred) over high heat until very hot. Add 1 tbsp olive oil. When oil is shimmering, add the steak. Sear without moving until a dark brown crust forms, about 3–4 minutes. Flip and add 1 tbsp unsalted butter; spoon the melted butter over the steak for 2–3 minutes for medium-rare (internal temp ~130–135°F / 54–57°C). Adjust time slightly for desired doneness. Remove steak to a cutting board and rest 5–7 minutes.
Slice steak
After resting, slice steak thinly across the grain into 1/4-inch slices. Keep warm while toasting bread and assembling sandwiches.
Bread & assembly
Assemble sandwiches
Spread a generous layer (about 1–2 tbsp) of the Boursin mixture on the bottom half of the toasted baguette. Top with a layer of caramelized onions (about 2–3 tbsp). Arrange the sliced strip steak over the onions. Drizzle 1–2 tsp of the balsamic reduction over the steak (adjust to taste). If desired, add fresh parsley or microgreens for brightness. Close the sandwich, press lightly, and slice in half if serving two portions.