If you're a vegetarian, you probably learned how to cook the following three dishes when you decided to go meatless: rice and beans; stir-fried vegetables with tofu; and, of course, portobello mushroom "burgers." You know the ones I mean: portobello mushroom caps, seasoned and grilled if you're lucky, bland and watery if you're not, thrown on a cheap supermarket bun and likely doused in ketchup and mustard, because, you know, they're burgers, right? Maybe it still happens to you today: you show up at a barbecue, having advised your host that you don't eat meat, and find him or her happily proffering the soggy mushrooms, which as likely as not were grilled right next to a mess of sausages, rendering them pretty much non-vegetarian, anyway. Sound familiar?
Although I'm not a vegetarian, I've cooked and eaten my fair share of portobello burgers, and I actually think I make a mean one. Nevertheless, I think it's high time we stop calling mushrooms "burgers" simply because they're round and fit nicely on a hamburger bun. There's absolutely nothing wrong with grilling a mushroom cap and sticking it between some bread, but why don't we call it what it is: a sandwich? And while we're at it, why don't we ditch the standard burger condiments and top our mushrooms with some flavors and textures that actually complement what is, when properly cooked—a juicy, flavorful, and earthy anchor for a great sandwich?
This recipe relies on a highly seasoned, grilled portobello—no bland, barely cooked (or cooked-to-death) mushrooms here. Once the base of the sandwich is perfect, it's time to get rid of the airy supermarket burger bun, and do the 'wich right by using a fresh, chewy focaccia roll. Then we can think about appropriate toppings: in this case a creamy, lemony white bean spread accented with fresh rosemary, with tender, peppery leaves of baby arugula piled on top. Once you try this portobello sandwich, you might never let your friends serve you a crappy mushroom burger again.