In a large mixing bowl whisk together soy sauce, pineapple juice, lime juice sesame oil, honey, sriracha, garlic, and ginger until smooth and combined. Add in skirt steak and coat well with marinade. Transfer to a large ziplock bag or cover marinade with plastic wrap. Refrigerate for 1 hour.

Heat a grill pan or cast iron skillet coated with oil on medium-high heat. Remove steak from marinade (reserve marinade) and grill for 1-2 minutes on each side. Remove from pan and let steak rest for 3-5 minutes.

Pour remaining marinade into a small sauce pan. Heat on medium heat until sauce has thickened and reduced, about 5 minutes.

Cut steak into trips or cubes and add in 1/4 cup onto each tortilla. Top steak with diced radishes, pineapple chunks and fresh cilantro. Drizzle with thickened marinade sauce and serve.