anyway. here's a recipe for a marinated portobello sandwich. don't follow it without changing a lot, i haven't made this since 2014 and i don't actually know how to cook anymore
step 1: get some portobellos and scoop out the gills and pop off the stalk. cut into thin strips and soak in olive oil, balsamic vinegar, garlic, and spices overnight.
step 2: once it's done marinading, toss the mushrooms into a pan with more olive oil on a decent heat and cook through, watch them shrink and gain a bit of color. probably don't salt them until they're done cooking, apparently that's bad
step 2.5: consider turning the leftover marinade liquids into a sauce. heat and add your favorite thickening agent, and maybe add some extra flavor like a fancy soy sauce. once it's thick, add it to the pan with the cooked mushrooms.
step 3: assemble sandwich. preferably using a bread sturdy enough to not go soggy easily. you can toast the bread if you like. add a layer of pesto on each slice, then add the mushrooms, top with a mix of salad greens, slivered onions, roasted red pepper, and feta. if you like raw tomato on your sandwich they'd probably work too. put the other bread slice on top
step 4: serve with fried tofu, carrot sticks, a plum, and cashews. consider either a strong tea or a weak cider.