I've seen a few recipes for portobello burgers using marinades and I have also used them myself in the past with mixed results. My thought with using a marinade, especially an oil or vinegar based marinade is wont it either get spongy or filled with oil and/or wouldn't vinegar just destroy the mushroom? Without any fat to break down, isn't the oil just getting absorbed? What is the angle to take with these? Steven raicheln in the grill bible has a marinade which he says for up to 3 hours. Times, elements and guidelines? Anyone?
