Press tofu: Wrap tofu with an absorbent towel and place it between 2 chopping boards. Place a heavy object on the top board. Leave it undisturbed for about 15 minutes, while you chop and prep the other ingredients.
Mash tofu: After 15 minutes, take out the tofu and crumble it. The easiest way to do it is to dice the tofu and crush the cubes with your hands. You can also use a potato masher.
Mix dark and light soy sauce, brown sugar, salt and water in a bowl. Whisk until the palm sugar dissolves. Keep aside.
Pound the garlic and chillies using a mortar and pestle until you get a crumbly paste.
Heat peanut oil in a wok or skillet. When the oil is hot, add chilli garlic paste and fry on medium heat for 2 minutes.
Increase the flame to high and add crumbled tofu. Do not stir immediately. Wait for 2 to 3 minutes, then stir.
Repeat (waiting and stirring) until tofu starts changing color. It would take about 6 to 9 minutes in total.
Add onions and bell pepper. Stir-fry on high for about 5 minutes.
Add the prepared sauce. Reduce flame and simmer until the sauce thickens.
Turn off the flame and mix in Thai basil leaves.
Mashing tofu: Do not mash tofu too much. You need those bits and pieces for texture.
Pounding garlic and chillies: Mortar and pestle gives the best results. If you don’t have a mortar, place in a ziploc bag and crush using a heavy object.
Cooking tofu: Cook on a high flame and DO NOT keep stirring it. Allow it to brown, then stir. Repeat until it gets browned uniformly.
Turn off the flame as soon as you add basil leaves. Overcooked basil leaves tend to become chewy.
Make more exciting main dishes using this basil tofu stir fry as the basic recipe: Thai basil tofu fried rice, tofu basil noodles, basil tofu lettuce wraps. (Instructions given inside the post above.)