Wrap the tofu block in a clean kitchen towel or several layers of paper towels. Place a heavy skillet or cutting board on top and let sit for 20-30 minutes to remove excess water. This step is crucial for crispy tofu. Once pressed, slice into ½-inch thick pieces.
Cut four 18-inch sheets of heavy-duty aluminum foil. Lay them flat on your counter or work surface.
Divide ingredients evenly among the four foil sheets in this order: Start with potato slices on the bottom, add tofu slices next, then top with onion, zucchini, bell pepper, and green beans. Drizzle each packet with ½ tablespoon olive oil. Sprinkle with Asian spice mix, salt, and pepper.
Bring the long sides of the foil together and fold over twice to seal. Fold in the short ends, leaving a small air pocket at the top for steam circulation. Make sure the packets are sealed well but not too tight.
Heat your grill to medium-high heat (around 400°F).
Place the foil packets directly on the grill grates. Close the lid and cook for 10-12 minutes. You should hear a faint sizzle after about 8 minutes, indicating the tofu is crisping up.
Carefully remove packets from the grill using tongs (they'll be very hot). Let cool for 1-2 minutes, then carefully open the packets, watching for hot steam. Give each packet a gentle shake to coat the vegetables in the flavorful juices. Drizzle with your choice of sauce if desired and serve immediately.