- 3 English-style bone-in beef short ribs (about 3 1/2 pound)
- Kosher salt, freshly ground pepper
- 1 medium sweet onion (such as Vidalia), thinly sliced
- 3/4 cup fresh orange juice
- 1/3 cup fresh lime juice
- 1/3 cup olive oil
- 1/2 cup chopped fresh flat-leaf parsley, plus leaves for serving
- Flaky sea salt (such as Maldon)
- 1 teaspoon finely grated lemon zest
- Season ribs generously with kosher salt and pepper. Place in a shallow baking dish with onion, orange juice, lime juice, oil, and 1/2 cup chopped parsley; toss to coat.
- Cover and chill at least 3 hours.
- Let ribs sit at room temperature 1 hour before grilling.
- Prepare grill for 2-zone heat (for a charcoal grill, bank coals on 1 side of grill; for a gas grill, leave 1 or 2 burners off).
- Remove ribs from marinade, scraping off excess, and grill over direct heat, turning occasionally, until charred on all sides, 15–20 minutes.
- Move ribs to indirect heat and grill, bone side down, until an instant-read thermometer inserted into thickest part registers 130° for medium-rare, 5–10 minutes (cooking past this point will yield tough meat). Transfer to a cutting board and let rest 10 minutes.
- Cut meat from bone and slice thinly against the grain (this step is key for pleasantly chewy bites); season with sea salt and pepper. Serve topped with lemon zest and parsley leaves.
- Do ahead: Ribs can be marinated 1 day ahead. Keep chilled.