Press the cubed Tofu with a paper towel for drainage. Set aside.
Heat sesame oil in a large pan or wok over medium-high heat, add garlic and onion until fragrant (about 1 minute).
Add bell peppers, broccoli florets, carrots, snow peas to the same pan. Stir fry for about 3 minutes.
Push vegetables to one side of the wok or pan and add pressed cubed Tofu on other side while stirring occasionally until golden brown (about 5-7 minutes).
Pour soy sauce, cooking stock/water over everything in even spoonfuls.
Continue to stir fry for another few minutes till all ingredients are well coated and thoroughly heated. Season with salt & pepper as per taste.