Preheat the oven to 450°F. Wash and dry the fresh produce. Lightly coat the tray(s) with a drizzle of olive oil. Using your hands, carefully separate the rice cakes. In the tray(s), combine the spinach, soy-miso sauce, sautéed aromatics, kimchi, rice cakes, and as much of the gochujang as you'd like, depending on how spicy you'd like the dish to be. Stir to combine. Add 1 tablespoon of water to the tray (or to each tray for 4 servings). Season with salt and pepper; stir to thoroughly combine.

Add the beef (tearing into bite-sized pieces before adding) in an even layer. Tightly cover the tray(s) with foil and bake, 18 to 20 minutes, or until the beef is cooked through and the rice cakes are tender. Remove from the oven. Carefully remove the foil. Add the crème fraîche and stir until combined. Let stand at least 3 minutes. Serve the baked tray(s) garnished with the sesame seeds. Enjoy!