Begin by pressing the tofu to remove excess moisture. Wrap it in a clean kitchen towel and place a heavy object on top for about 15-20 minutes.
Once pressed, cut the tofu into 1-inch cubes and toss them in a bowl with cornstarch, ensuring they are evenly coated.
Heat 1 tablespoon of vegetable oil in a large skillet or wok over medium-high heat. Add the cubed tofu in a single layer and fry until golden brown on all sides, about 8-10 minutes. Remove and set aside.
In the same skillet, add the remaining tablespoon of oil. Once hot, add the sliced red and green bell peppers along with the snap peas. Stir-fry for 3-4 minutes until the vegetables are just tender but still vibrant.
Add the minced garlic and grated ginger to the pan and stir-fry for another minute until fragrant.
Return the browned tofu to the skillet, then pour in the sweet chili sauce, soy sauce, rice vinegar, and sesame oil. Toss everything together gently to coat and heat through, about 2-3 minutes. Taste and season with salt and pepper if needed.
Serve the stir-fry over cooked jasmine rice, garnished with fresh cilantro if desired.