I love an open sandwich that’s bold without being fussy — this Savory Steak, Tomato and Sweet Onion Open Sandwiches Delight hits that mark every time. It combines a juicy, seared steak, ripe tomato, and caramelized sweet onion on toasted bread for contrast and crunch. I’ve made versions of this many times and tweak the sear and onion to suit the day.
Why Make This Recipe
- Fast weeknight dinner: sear steak for 4–6 minutes and assemble in under 25 minutes.
- Big flavor, simple ingredients: quality steak, ripe tomato, and sweet onion deliver temperature and texture contrast.
- Balanced meal: protein from the steak, fresh tomato for acidity, and whole-grain bread for fiber.
- Entertaining-friendly: it looks rustic but comes together quickly when guests arrive.
- Personal note: I love this recipe because caramelizing the onions brings out a natural sweetness that makes each bite feel indulgent and homey. Also try it alongside slow cooker French dip nights when you want a sandwich theme.
Recipe Overview
- Prep time: 10 minutes (slice and season).
- Cook time: 12–15 minutes (onion 8–10, steak 4–6).
- Total time: 22–25 minutes.
- Servings: 4 open sandwiches.
- Difficulty: Easy.
- Method: High-heat searing (cast-iron skillet) for steak, low-simmer caramelization for onions, toast bread under broiler or in toaster oven, and assemble.
My Experience Making This Recipe
I tested this recipe across several steak cuts and browning methods to land on a reliable shortcut that preserves juice and flavor. The biggest discovery: thin-sliced steak sears faster and stays tender when you rest it briefly; don’t overcook. I also learned that starting onions in a mix of oil and butter at medium heat prevents burning and speeds caramelization.
How to Make Savory Steak, Tomato and Sweet Onion Open Sandwiches Delight
Start by thinly slicing 1 lb flank or skirt steak against the grain, season with salt and pepper, and let it sit 20 minutes at room temperature. Heat a heavy skillet (preferably cast iron) over medium-high until smoking slightly, add 1 tbsp neutral oil, and sear steak slices 1–2 minutes per side for medium-rare (aim for 130–135°F internal). Meanwhile, slice 1 large sweet onion thin and caramelize it in a separate pan over medium-low with 1 tbsp butter and a pinch of salt for 8–10 minutes until golden. Toast 4 slices of sturdy bread (400°F in the oven for 4–6 minutes or under a broiler for 1–2 minutes), then layer bread with a light smear of aioli, tomato slices, steak, and onions. Rest steak 5 minutes before slicing to keep juices in the meat.
Expert Tips for Success
- Use an instant-read thermometer: pull the steak at 125°F for medium-rare after resting (carryover will raise it to 130–135°F).
- Thin slices sear quickly: cut steak across the grain into 1/4-inch slices to stay tender.
- Heat management for onions: cook onions low and slow (medium-low) so they sweeten instead of burning; add 1 tsp sugar at the 6-minute mark only if your onions aren’t sweet enough. Also check out a technique for getting extra-sweet onions in this onion guide.
- Equipment: use a heavy skillet (10–12 inch cast iron) for the best sear and a serrated knife to slice tomatoes without squashing them.
- Bread choice matters: select a dense, crusty loaf (like country sourdough) that holds juices but won’t get soggy.
How to Serve Savory Steak, Tomato and Sweet Onion Open Sandwiches Delight
- Casual dinner: serve with a simple green salad and vinaigrette for acidity.
- Weekend brunch: add a soft fried egg on top and pair with a warm baked tomato dish like baked feta eggs with tomatoes and spinach.
- Party tray: make smaller crostini versions and hold the steak in a warm pan while guests assemble.
- Presentation tip: stack ingredients slightly off-center on each slice and finish with flaky sea salt and chopped parsley for color and texture.
Storage and Reheating Guide
Store components separately for best results: keep cooked steak slices in an airtight container in the refrigerator for 3–4 days, caramelized onions for up to 5 days, and bread at room temperature or frozen for longer. To freeze steak, wrap tightly in foil and place in a freezer bag for up to 2 months; thaw overnight in the fridge. Reheat steak gently in a 300°F oven covered with foil for 8–10 minutes or slice and warm in a skillet with a teaspoon of oil for 1–2 minutes per side to avoid drying. Avoid reheating assembled sandwiches—toast the bread and rewarm ingredients separately before building.
Recipe Variations
- Gluten-free: use gluten-free hearty bread or toasted gluten-free baguette slices.
- Dairy-free: swap the butter in the onions for extra olive oil and use a dairy-free aioli.
- Vegetarian swap: replace steak with grilled portobello or marinated tempeh and keep caramelized onions for umami.
- Flavor twist: add thinly sliced roasted red peppers and a smear of horseradish mayo for a sharper finish.
Nutritional Highlights
- Good source of protein from the steak and vitamins from fresh tomato and onion.
- Depending on bread choice, this can provide fiber (choose whole-grain for more).
- Allergen note: contains gluten (bread) and often dairy (butter, aioli); adapt as noted in variations for gluten-free or dairy-free needs. Keep portion size to one open sandwich per person for a balanced meal.
Troubleshooting Common Issues
- Steak came out tough: you likely overcooked it or sliced with the grain. Next time, slice against the grain and aim for 125°F pull temperature for medium-rare.
- Onions burned quickly: your heat was too high. Cook onions on medium-low and stir every 1–2 minutes; add a splash of water if they stick.
- Bread soggy after assembling: toast bread longer and assemble just before serving, or serve toppings on the side for build-your-own sandwiches.
Frequently Asked Questions
Q: Which steak cut is best for quick-sliced open sandwiches?
A: Flank, skirt, or thinly sliced sirloin work best because they sear quickly and have great beefy flavor. Slice across the grain into 1/4-inch strips for tenderness and aim for medium-rare to medium doneness.
Q: How do I prevent the steak from losing its juices when cutting?
A: Rest the steak 5–10 minutes after cooking on a warm plate loosely covered with foil. Resting lets juices redistribute; cut only when it has cooled slightly and use a sharp knife to minimize tearing.
Q: Can I make components ahead of time for serving later?
A: Yes. Caramelized onions keep up to 5 days refrigerated, and steak slices keep 3–4 days. Toast bread just before serving. Store components separately in airtight containers to preserve texture.
Q: What’s the best way to get evenly caramelized onions?
A: Cook thinly sliced onions in a wide skillet over medium-low heat with a mix of oil and butter, stirring every few minutes. A pinch of salt helps draw out moisture; if browning too fast, lower the heat and add a splash of water to deglaze.
Conclusion
If you like hearty sandwiches and want a quick yet sophisticated meal, this open sandwich is a reliable go-to. For inspiration from a sandwich-focused shop and ideas for ordering or comparing regional styles, check out Capriotti’s Sandwich Shop – Order Online | Best Subs, Cheesesteaks ….
Savory Steak, Tomato and Sweet Onion Open Sandwiches Delight
- Total Time: 25 minutes
- Yield: 4 open sandwiches
- Diet: None
Description
A bold and flavorful open sandwich featuring juicy seared steak, ripe tomato, and caramelized sweet onion on toasted bread, perfect for a fast weeknight dinner or entertaining guests.
Ingredients
- 1 lb flank or skirt steak
- Salt and pepper
- 1 tbsp neutral oil
- 1 large sweet onion
- 1 tbsp butter
- 4 slices of sturdy whole-grain bread
- Ripe tomato slices
- Aioli (to taste)
Instructions
- Thinly slice the steak against the grain, season with salt and pepper, and let it sit at room temperature for 20 minutes.
- In a heavy skillet, heat the oil over medium-high heat until slightly smoking.
- Sear the steak slices for 1-2 minutes per side, aiming for medium-rare.
- Meanwhile, thinly slice the onion and caramelize it in a separate pan over medium-low heat with butter and a pinch of salt for 8-10 minutes until golden.
- Toast the bread in the oven at 400°F for 4-6 minutes or under a broiler for 1-2 minutes.
- Layer the toasted bread with a light smear of aioli, tomato slices, seared steak, and caramelized onions.
- Let the steak rest for 5 minutes before slicing to retain juices.
Notes
Use an instant-read thermometer to check the steak’s doneness. Thinly sliced steak sears quickly, so avoid overcooking. Cook onions low and slow for best results.
- Prep Time: 10 minutes
- Cook Time: 15 minutes
- Category: Main Course
- Method: Searing
- Cuisine: American