To prepare the tofu: Drain the tofu and use your palms to gently squeeze out some of the water. Slice the tofu into thirds lengthwise so you have 3 even slabs. Stack the slabs on top of each other and slice through them lengthwise to make 3 even columns, then slice across to make 5 even rows (see photos).
Preheat the oven to 400 degrees Fahrenheit and line a large, rimmed baking sheet with parchment paper to prevent the tofu from sticking.