Gently scrape out the dark gills with a spoon before marinating—this creates a larger surface area for the marinade to penetrate and prevents excess moisture that can make them soggy.

After marinating, pat the portobello caps completely dry with paper towels to achieve a caramelized crust and prevent steaming during cooking.

Brush corn oil directly onto the hot grill grate moments before cooking rather than only oiling the mushroom—this creates superior grill marks and prevents sticking.

Let the mushrooms sit in the marinade outside the refrigerator for optimal flavor absorption and even cooking, rather than cold marinating which slows penetration.

Reduce balsamic vinegar in a pan until syrupy, then drizzle over the grilled mushrooms for concentrated sweetness and an elegant restaurant-quality presentation.