Press the tofu to remove excess water, then cut it into cubes.
Heat vegetable oil in a skillet or wok over medium-high heat.
Add the tofu cubes and stir-fry until they become golden brown on all sides. This usually takes about 5-7 minutes.
Once the tofu is browned, remove it from the skillet and set it aside.
In the same skillet, add a bit more oil if needed. Sauté garlic and ginger until fragrant.
Add broccoli florets and bell pepper slices to the skillet. Stir-fry for 3-5 minutes until the vegetables are tender-crisp.
In a small bowl, mix soy sauce and sesame oil. Pour the sauce over the vegetables in the skillet.
If you want a thicker sauce, mix 1/2 tablespoon of cornstarch with a bit of water to create a slurry. Add it to the skillet and stir until the sauce thickens.
Add the cooked tofu back to the skillet and toss everything together until well coated.
Serve the stir-fry over 1 cup of cooked rice.
Garnish with sliced green onions and sesame seeds.