Wrap block of tofu in paper towels or a clean dish towel and squeeze out as much water as you can. If you have the time, use a tofu press for 30Min to remove excess liquid.
Cube the tofu and throw in a large bowl along with the cornstarch, salt, and pepper. Toss until coated.
Add vegetable oil to a large pan on medium-high heat. Fry the tofu until crispy and golden brown. I do this in batches to make sure they evenly brown. Remove tofu from the pan and place on a wire rack.
Large dice the red bell pepper and add to the same pan. Cook until charred and soft. Add in the diced pineapple and cook for an additional 2-3 minutes.
Whisk together all the sauce ingredients and add to the pan with red bell pepper and pineapple. Cook for 1-2 minutes until it starts to bubble and thicken. Toss in tofu and coat evenly.
Serve the Sweet & Sour Tofu with your choice of white or brown rice and top with thinly sliced scallions. Enjoy!