Add enough oil to a large pan for frying (about ½ - 1 inch high) and heat to medium temperature.Note: Skip if air-frying
Dice pressed tofu into 1 inch cubes and transfer to a medium sized mixing bowl.
Add cornstarch to the mixing bowl and season with salt and pepper. Gently stir so that all tofu pieces are coated.
Transfer the coated tofu to the pan with oil and cook on both sides until lightly browned then transfer to cooling rack or plate lined with paper towels to absorb excess oil. Set aside.Note: If air frying, transfer the coated tofu to your air fryer basket and spray with a neutral oil on both sides. Cook at 400° for 15 minutes. Set aside once finished.
In a separate pan over medium-low heat, begin warming the vegan butter. Once warmed, add in the minced garlic and sauté until fragrant.
Add in the agave, salt, pepper, apple cider vinegar and soy sauce. Now increase the temperature to medium high so that it begins to boil.
Stir in cooked tofu and coat thoroughly with the sauce. Once combined, remove from heat, garnish with optional fresh green onion and serve.