1/4 tsp Calabrian chili paste, harissa pasta or dried red chili flakes
4 or 5 fresh sprigs of Italian oregano
1/2 red onion, peeled and sliced thin
1 cup white or cider vinegar
1 tsp salt
1 tsp sugar
1 garlic clove
Marinade the steak
Place the steak in a shallow glass or ceramic dish and add soy sauce until it comes about halfway up around the steak. Season with fresh cracked pepper. Marinate in the fridge for 2 or 3 hours, flipping over occasionally to coat well.
Preheat the broiler in your oven and position the top rack 6-8 inches from the the broiler.
Cut the tomatoes either lengthwise or width-wise so that the tomatoes are of uniform height. Place on a sheet pan clustered in the center.
Place the sheet pan in the oven directly under the broiler. Broil for about 15 minutes, but check every 5 minutes to make sure the tomatoes are charring evenly. Slide the sheet pan around as needed. The tomato skins should be charred black.
Remove from the oven and let cool.
Once cool, the skins should just lift off with no trouble. Remove any thick greenish core from the tomatoes.
Heat 1 tbsp of oil in a small sauté pan over low heat. Mince the 2 garlic cloves and add to the sauté. Add the chilies to the pan and stir. Sauté the garlic until lightly browned, being careful not to burn.
Add the peeled tomatoes to the pan. Stir and break up the tomatoes. Add the fresh oregano to the pan.
Gently cook the sauce until it’s smooth and cooked through. Season with salt to taste.
Peel the red onion, removing the skin and thick outer layers. Cut the onion in half through the root end and retain half of the onion for another use. Thinly slice the remaining onion.
In a small sauce pot, add the vinegar, salt and sugar. Slice the garlic clove in half and add as well.
Bring the pot to a boil and then add the sliced onions. Reduce the heat to simmer and cook for about 10 minutes. Cover and let stand for 10 or more minutes.
Prepare the steak and serve
Remove the steak from the soy sauce and dry with paper towels.
Heat a cast iron frying pan large enough to hold the steak over a high flame until a few drops of water sizzle away immediately.
Add 1 tbsp of olive oil and carefully swirl around. Reduce the heat to medium and add the steak. Sear each side until nicely browned and the internal temperature in the thickest part reads 135-degrees.
Remove the steak to a dish and cover with foil. Set a timer for 10 minutes.
Add the tomato sauce to the pan that held the steak and stir in with the pan juices. If the sauce is too thick, add a little water or wine to thin it out.
Taste the sauce and adjust for salt and pepper.
Once the steak has rested, slice across the grain. Dress with the sauce. Drain the onions and garnish on top with the pickled onions.