Roasted Portobello Sandwich

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   ["Preheat the oven to 400 degrees.", "", "Heat the butter and olive oil over medium heat in a large pan or skillet (avoid the nonstick ones if you can help it). Add the onions and turn the heat to medium-low. Cook, stirring INfrequently (that's right, just relax and let 'em do their thing) until the onions are a deep golden-brown color, approximately 20 minutes. Remove from the heat and set aside.", "", "While the onions carmelize, clean the mushroom caps. On a cookie sheet, drizzle the mushrooms with olive oil, salt and pepper. Roast at 400 for 8 - 10 minutes until they have reduced in size a little bit and look ""roasty toasty.""

* Per serving · 4 servings · Values may vary.