Bring a small pot of water to a boil and cook the egg for 6 minutes, then transfer to an ice bath, peel, and set aside.
In a small bowl, whisk together the gochujang, tamari, minced garlic, and grated ginger to create the glaze.
Heat the sesame oil in a large skillet over medium-high heat and sear the thinly sliced pork until browned and cooked through.
Pour the gochujang sauce over the pork in the skillet and toss for 1 minute until the glaze becomes thick and glossy.
Add the spinach to the pan and sauté for 30 seconds until just wilted.
Assemble the bowl by layering the spinach, kimchi, and sliced cucumber, then top with the glazed pork, the halved egg, and a sprinkle of sesame seeds.