Place cashews in a bowl and add 1/2 cup boiling water. Let stand while you prepare the rest of recipe.
Combine quinoa and broth in a saucepan. Bring to a boil over high heat, cover and reduce heat to low. Cook until liquid is mostly absorbed, about 13 to 15 minutes. Remove from heat, and let quinoa steam, covered, for 10 minutes. Stir in cilantro, 1 tsp. lime zest, and 1 Tbsp. lime juice. Season with a pinch of salt, if desired.
Meanwhile, heat olive oil in a large skillet over medium. Add bell peppers, onion, and poblano pepper; cook 7 to 8 minutes, until softened. Season with chili powder, 1/2 tsp. cumin, and 1/4 tsp. salt.
Place black beans in a bowl. Stir in remaining 1/4 tsp. cumin, 1/4 tsp. salt, 1 Tbsp. lime juice, and garlic powder. Cover with a damp paper towel and microwave until warm, about 60 to 90 seconds, stirring once halfway through.
Place cashews and soaking liquid in a high power blender. Add chipotle pepper, orange juice, and 1/4 tsp. salt; blend on high speed until smooth and creamy. Taste and add a pinch more salt, if needed.
Prepare bowls by dividing quinoa evenly between 4 bowls. Divide black beans and pepper and onion mixture between each bowl, and drizzle with chipotle sauce. Garnish with sliced avocado and additional fresh cilantro, if desired.