Cast Iron Filet Mignon with Caramelized Onions and Blue Cheese
Premium filet mignon steaks seared in a cast iron skillet and topped with a rich blue cheese cream sauce, caramelized onions, and crispy bacon. The extended caramelization process creates deeply sweet onions that balance the tangy blue cheese and smoky bacon. Perfect for special occasions or romantic dinners when you want restaurant-quality results at home. The cast iron technique ensures a perfect sear while the cream sauce adds luxurious richness to these tender cuts.
Ingredients
- 4 slices bacon, roughly chopped
- 3 medium yellow onions, thinly sliced
- 4 tablespoons salted butter, divided
- 4 8-ounce filet mignonsribeye steaks1:1none
more marbling, different texture
- ½ teaspoon salt
- 1 teaspoon black pepper
- 1 clove garlic, minced
- 1 cup heavy cream
- 5 ounces blue cheese, crumbles
- 1 teaspoon Worcestershire sauce
Instructions
- 1
Heat cast iron skillet on high heat and sauté chopped bacon until browned and crispy, then remove leaving grease behind
- 2
Melt butter in skillet with bacon grease on medium-low heat, add sliced onions and sauté until extremely soft and caramelized, stirring frequently to prevent burning
- 3
Add bacon back to pan with onions to heat through, then remove mixture and set aside
- 4
Season steaks with salt and black pepper, heat same cast iron pan on high until smoking
- 5
Turn heat to medium and immediately add steaks, cook per side without moving to ensure proper searing
- 6
Remove steaks and let rest on plate with foil tent, add remaining butter and minced garlic to skillet on low heat until fragrant
- 7
Add heavy cream, blue cheese crumbles, Worcestershire sauce, and remaining black pepper, stir and bring to low rolling boil, cooking until sauce thickens
- 8
Return steaks to pan with sauce and top with caramelized onions and bacon, or plate steaks and ladle sauce over top
Tips
Don't move the steaks during the initial 5-minute sear to develop a proper crust and prevent sticking to the cast iron surface.
Caramelize onions slowly over 25 minutes with frequent stirring to achieve deep sweetness without burning or bitter flavors.
Let steaks rest under foil after cooking to redistribute juices before adding back to the sauce for optimal tenderness.
Good to Know
Refrigerate cooked steaks up to 3 days. Reheat gently in low oven to avoid overcooking.
Caramelize onions and cook bacon up to 2 days ahead. Reheat before serving. Cook steaks fresh for best results.
Serve immediately while steaks are hot with the warm blue cheese sauce. Pair with roasted vegetables or garlic mashed potatoes.
Common Mistakes
Use medium heat after initial searing to avoid burning the outside while undercooking the center.
Don't skip the resting period or juices will run out when cutting into the steaks.
Keep sauce on low heat to prevent blue cheese from breaking and becoming grainy.
Substitutions
Dairy-Free Swaps
General Alternatives
more marbling, different texture
FAQ
Can I use a different type of steak?
Yes, ribeye or New York strip work well but may need different cooking times due to thickness variations. Adjust timing accordingly for your preferred doneness.
What if I don't have blue cheese?
Substitute with gorgonzola for milder flavor or goat cheese for tanginess. Feta works too but will create a different flavor profile entirely.
How long will the caramelized onions keep?
Store caramelized onions in the refrigerator for up to one week or freeze for up to three months. Great for multiple uses beyond this recipe.