Bring a small pot of water to a boil, carefully lower the egg into the water, and simmer for 6 minutes and 30 seconds before transferring to an ice bath.
In a small mixing bowl, whisk together the gochujang, tamari, garlic powder, and ginger powder to create a smooth spicy glaze.
Trim any excess fat from the pork tenderloin and cut into bite-sized cubes.
Heat the sesame oil in a large non-stick skillet over medium-high heat and sear the pork cubes for 4-5 minutes until browned and cooked through.
Reduce the heat to low, pour the gochujang glaze over the pork, and toss for 1 minute until the sauce thickens and coats the meat.
Remove the pork from the skillet and quickly toss the fresh spinach into the warm pan for 30 seconds until just wilted.
Peel and halve the soft-boiled egg.
Assemble the bowl by layering the cooked brown rice with the glazed pork, wilted spinach, and kimchi.
Top with the jammy egg halves and a sprinkle of sesame seeds.