These veggie burgers may be the best meatless dinner you have all week. Black beans form the traditional base, but unlike the usual recipes that use breadcrumbs or eggs to bind, our secret ingredient is actually a blend of brown rice, almond meal, and a little cheese. The result is a spicy, savory patty with fiber, protein and extra veggies.
In small saucepan, combine frozen rice with 1/4 cup water and cook, covered, until rice is very soft, about 8 minutes. Transfer rice to bowl of food processor.
In heavy medium skillet, preferably cast iron, heat 1 tablespoon oil over medium-high heat. Add onion and pepper, and cook until onion is translucent, 4 minutes. Add garlic and cook until onion is soft, 4 minutes. Transfer vegetables to bowl of food processor.
Add beans to food processor and pulse to chop mixture coarsely. Add almond meal or almonds and chili pepper and pulse just to blend, 6 times. Add cheese and pulse to blend, 4 times. Scoop burger mixture into medium bowl; it will be quite sticky. Season mixture to taste with salt and pepper.
Lightly moisten your hands and shape burger mixture into 6 patties, arranging patties on a plate. Burgers taste best when covered with plastic wrap and refrigerated 8 to 24 hours to let flavors meld.
To cook burgers, heat remaining tablespoon oil in skillet on medium high heat. Add burgers and cook until crusty and dark brown on bottom, 2 minutes. Carefully turn burgers and cook until crusty on second side, 2 minutes.To serve, open pita breads and arrange 1/2 cup arugula on each bottom. Add cooked burger and top with onion and tomato slices. Serve immediately.