Make the chimichurri sauce by combining the parsley, oregano, garlic, red wine vinegar, olive oil, and red pepper flakes in a food processor or blender. Blend until well combined but still a bit chunky.
Press the tofu to remove excess moisture. Cut into ½-inch thick slices.
Preheat grill to medium-high heat. Brush the tofu slices with the chimichurri sauce on both sides.
Grill the tofu for 3-4 minutes per side, until charred and cooked through.
Serve the grilled tofu with the remaining chimichurri sauce.
