Toss scallion, cherry tomatoes, olive oil, ginger, sesame oil, kosher salt, rice vinegar, soy sauce, and sugar in a bowl until combined. Let it sit while you toast the bread.
STEP 2
Heat olive oil in a skillet over medium. Fry the bread until golden brown, about 6 minutes, turning halfway. Rub garlic on one side and cut into thirds.
STEP 3
Arrange crostini, spoon tomato mixture on top, and drizzle with sesame oil. Add torn basil and sprinkle with flaky sea salt if desired.