Slice the pork tenderloin into 1-inch cubes and place them in a medium glass bowl.
In a small jar, whisk together the gochujang, tamari, honey, sesame oil, grated ginger, and minced garlic until smooth.
Pour the marinade over the pork, tossing well to coat every piece, and let it sit for at least 20 minutes.
While the pork marinates, slice the zucchini into half-inch thick rounds and season lightly with sea salt and black pepper.
Thread the marinated pork and zucchini rounds onto skewers, alternating between the meat and the vegetable.
Preheat a grill or cast-iron grill pan over medium-high heat and lightly coat with a touch of oil if needed.
Grill the skewers for 3 to 4 minutes per side, brushing with any remaining marinade, until the pork is cooked through and the edges are crispy.
Remove from heat and garnish with toasted sesame seeds and thinly sliced green onions before serving.