Cook onion and garlic in olive oil, add ginger, soy sauce, sesame oil, rice vinegar, pepper, and red pepper flakes. Thicken sauce with cornstarch mixed with water.
Cook tilapia fillets in the sauce for 4-5 minutes per side until flaky.
Assemble bowls with lentils, vegetables, and tilapia. Drizzle with additional sauce if desired.
Notes
Feel free to customize vegetables or spice levels to taste.