Prepare the dressing by mixing all ingredients into a bowl and adjust taste if needed. Place cubed tofu into a bowl and pour 1/4 of the dressing over it and marinade for 20 minutes. Set aside rest of the dressing.
Heat a little oil in pan and saute garlic until fragrant. Gently add the marinated tofu and cook until tofu has browned and marinade evaporated. Remove from heat and chill in refrigerator for an hour.
In a large bowl, toss the sliced cucumber, capsicum, spring onions, cilantro and some of the peanuts together with dressing. Gently fold in the chilled tofu. Sprinkle leftover peanuts on top and serve.