Drain and rinse bamboo shoots. Slice them into thin slices if they are not already.
In a skillet over medium heat, add sesame oil followed by garlic and ginger. Let cook for 2 minutes.
Add bamboo shoots, brown sugar, bonito flakes, mirin, soy sauce, and water. Bring to a boil, then let simmer (uncovered) for 10 minutes.
Discard bonito flakes and serve bamboo shoots atop ramen or as a side dish. Store leftovers in an airtight container and consume them within one week.