Add the olive oil and sesame oil to a small saucepan set over medium-low heat.
Add the garlic and cook, stirring frequently, until golden brown and fragrant, about 2 minutes.
Whisk in the orange marmalade, soy sauce, rice wine vinegar and orange juice.
In a small bowl, whisk together the cornstarch with 1 tablespoon water.
Increase the heat to medium-high and whisk in the cornstarch mixture. Bring the mixture to a boil until it thickens slightly, about 3 minutes. Transfer it to a serving bowl.
Serve the chicken with the sauce for dipping or toss the chicken in the sauce to coat.