Preheat the oven to 200 C or 400 F. Place about 8 wooden skewers in water to soak. We do this so that while in the oven, the skewers do not burn.
Line a baking dish with foil, and top with a rack (see video!)
saute the onion with the crushed garlic in 2 tbsp oil (I like to use sesame oil or peanut oil, vegetable oil works fine too) until soft, about 5 minutes.
Combine the chilli flakes, brown sugar, lemon juice, peanut butter, coconut milk, and soy sauce until well incorporated.
Stir in the onions and garlic, then add in the tofu chunks.
When everything is well mixed, skewer the tofu, and place on the rack.
Bake for 3-4 minutes on each side. (this means you’ll have to turn the tofu 4 times.)