Combine the teriyaki marinade, pineapple, cilantro, jalapeno, garlic cloves, crushed red pepper, and lime zest in a blender. Blend until smooth.
In a separate container, steep the sweet tea bag in 1 cup of cool water for at least 30 minutes, or until the tea reaches a murky brown color.
Once the tea is steeped, combine it with the blended marinade.
Place the trimmed skirt steak in the tea-teriyaki marinade. Ensure the steak is fully submerged. Let it marinate for 3 hours.
After marinating, remove the steak from the marinade and lightly pat it dry.
Season the steak generously on both sides with sea salt and black pepper.
Heat a cast-iron skillet over medium-high heat. Add coconut oil to the pan.
Sear the skirt steak for 7 to 9 minutes on each side, or until it reaches your desired level of doneness.