Bring 2 cups of water to a boil in a small pot. Add the instant ramen noodles (reserve seasoning packet) and cook for 2 minutes, stirring occasionally.
While noodles cook, prepare the egg: bring a small saucepan of water to a boil, gently lower the egg in, and boil for 6 minutes for a soft-boiled egg. Transfer to ice water, peel, and halve.
In a bowl, combine the seasoning packet, sesame oil, and soy sauce. Pour the cooked noodles and broth over the seasoning mixture and stir.
Add fresh spinach to the hot broth and let it wilt. Top with sliced meat (if using), soft-boiled egg, green onion, and nori pieces. Serve immediately.
Tips
For extra flavor, add a pat of butter or a drizzle of chili oil.
Customize with leftover vegetables like corn or bok choy.
If you prefer a poached egg, crack the egg into the simmering broth during the last minute of cooking.