In a small mixing bowl, whisk together the gochujang, tamari, rice vinegar, honey, garlic powder, and ginger powder until smooth and combined.
Heat a large non-stick skillet over medium-high heat. Add the finely diced pork belly and cook for 4-5 minutes until the fat has rendered and the pieces are golden and crispy.
Add the cubed pork tenderloin to the skillet with the pork belly. Sauté for 5-7 minutes, stirring occasionally, until the tenderloin is browned on all sides and cooked through.
Reduce the heat to medium and pour the gochujang sauce over the meat. Toss continuously for 1-2 minutes until the sauce thickens into a glossy, vibrant glaze that coats every piece.
While the meat rests for a moment, lightly toast the corn tortillas in a separate dry pan over medium heat for 30 seconds per side until they are soft and slightly charred.
Assemble the tacos by filling each warm tortilla with a generous portion of the spicy pork mixture. Top with the shredded cabbage, sliced green onions, and a sprinkle of sesame seeds for a fresh crunch.