01 - Rinse rice under cold water. In a saucepan, combine rice, water (or broth), and a pinch of salt. Bring to a boil, reduce heat to low, cover, and simmer for 15 minutes. Remove from heat, let stand 5 minutes, then fluff with a fork. Stir in lime juice and cilantro if using.
02 - In a bowl, toss sliced steak with olive oil, chili powder, cumin, garlic powder, smoked paprika, salt, and pepper until evenly coated.
03 - Heat a large skillet or grill pan over medium-high heat. Cook steak slices in a single layer for 2–3 minutes per side, until browned and just cooked through. Remove from heat and tent with foil.
04 - In a saucepan, melt butter over medium heat. Whisk in flour and cook for 1 minute. Gradually whisk in milk until smooth. Cook, stirring, until thickened (2–3 minutes). Lower heat and add cheeses, smoked paprika, cayenne (if using), and salt. Stir until cheese is melted and sauce is smooth.
05 - Divide rice among 4 bowls. Top with steak slices, black beans, tomatoes, corn, avocado, and any other desired toppings. Drizzle generously with warm queso sauce. Garnish with cilantro and a wedge of lime.