Toast the sesame seeds in a dry pan over medium-high heat for 4 minutes, stirring constantly, until golden brown. Let cool.
Finely mince the garlic. Thinly slice the scallion.
Combine the sesame seeds, garlic, scallion, soy sauce, oil, vinegar, red pepper flakes, and agave syrup in a small bowl or a jar. Store in the refrigerator for up to 1 week.