Slice zucchini lengthwise into quarter-inch planks for even cooking and maximum surface area exposure. Pat dry with paper towels to remove excess moisture, which prevents proper charring and ensures texture consistency throughout cooking time.

Whisk together olive oil, minced garlic, kosher salt, black pepper, red pepper flakes, and dried oregano in a small bowl. This mixture creates a flavorful marinade coating that adheres during grilling and enhances the natural vegetable sweetness.

Brush both sides of each zucchini plank generously with the garlic-oil mixture, ensuring complete coverage. Arrange planks on a clean plate and let rest for five minutes while your grill preheats to medium-high heat, approximately 425 degrees Fahrenheit.

Place charred grilled zucchini directly on oiled grill grates, working in batches if necessary to avoid overcrowding the cooking surface. Grill for three to four minutes without moving, allowing deep caramelization and char development on the first side before flipping.

Flip each plank carefully and grill the opposite side for an additional two to three minutes until fork-tender and marked with beautiful char lines. Transfer cooked planks to a serving platter immediately to prevent overcooking and maintain ideal texture.

While still warm, drizzle the grilled vegetables with fresh lemon juice and scatter chopped fresh basil across the surface. Top with grated Parmesan cheese for a finishing touch that adds richness and umami depth.