Preheat the oven to 400°. In a food processor, pulse the parsley, garlic and jalapeño a few times, until the mixture is finely chopped. Add the red pepper flakes, lime juice, vinegar, 1 cup of the olive oil, 1 teaspoon of salt and 1/2 teaspoon of pepper and process until combined. Pour half of the sauce into a bowl and add the sliced red onion and tomato wedges. Save the remaining sauce for passing at the table.
Heat a large, heavy-bottomed skillet or cast-iron skillet over medium-high heat. Pat the steaks dry with a paper towel and season with salt and pepper. Add the remaining tablespoon of olive oil to the pan and when the pan is hot, cook the steaks for 5 minutes per side for medium-rare (cook in batches if your pan isn’t large enough to hold them all). Set the steaks aside on a cutting board to rest for at least 5 minutes before carving. Thinly slice the steaks across the grain and toss with the onion-tomato mixture.
Arrange the split rolls, cut side up, on a large baking sheet and spoon the steak mixture onto 1 side; scatter the goat cheese over the steak. Bake until the bread is toasty and the cheese is melted, about 7 minutes. Serve the sandwiches with the extra sauce on the side.