Place tofu onto a plate and place another plate on top. Set a 3- to 5-pound weight on top (a container filled with water works well). Press tofu for 20 to 30 minutes; drain and discard the accumulated liquid.
Heat a large skillet over medium heat. Add olive oil and onion; saute until translucent, about 5 minutes. Add dry vegetable soup mix and stir to coat. Crumble tofu into the skillet; break apart any large chunks with a wooden spoon. Season with salt and pepper. Cook and stir until golden brown and flavors have been absorbed, 5 to 10 minutes. Transfer to a serving dish and garnish with parsley.