In a wok or large skillet, heat the peanut oil over medium-high heat until almost smoking. Add the garlic and stir-fry until just fragrant, about 10 to 15 seconds. Add the bok choy and stir-fry for 2 minutes or until crisp-tender.
Remove the pan from the heat and drizzle with the sesame oil and sprinkle with salt. Transfer to a serving dish and sprinkle with the toasted sesame seeds to serve.