Place the Bok Choy in a colander and rinse with cold water, removing any grit from between the leaves. Pat dry with a kitchen towel and cut each Bok Choy in half lengthwise.
Heat the sesame oil in a large skillet over medium-high heat and stir-fry the garlic slices and dried chilies for about 30 minutes until fragrant. Add the Bok Choy in a single layer cut-side down and cook until the bottoms start to brown, about 2 minutes.
Flip the Bok Choy over and cook until the stalks begin to soften about 2 additional minutes. Reduce heat to medium-low and add the soy sauce to the skillet. Simmer for 1 minute.
Transfer to a platter and garnish with sesame seeds. Serve immediately.