In a bowl, combine sliced steak with olive oil, chili powder, cumin, salt, and pepper. Let marinate for at least 15 minutes.
Heat 1 tbsp olive oil in a skillet over medium heat. Add diced onion, cook until translucent. Add garlic, sauté for 1 more minute.
Stir in rice, chili powder, cumin, salt, and pepper. Toast for 2-3 minutes. Pour in broth, bring to boil, then cover and simmer on low for 18-20 minutes.
In a separate skillet, cook steak in batches over high heat, 2-3 minutes per side. Set aside when done.
For homemade queso: melt butter, stir in flour and cook 1 minute. Slowly add milk while whisking. Add cheese and chilies, stir until melted and smooth. Season with salt.
To serve: Layer rice on a plate or bowl, top with cooked steak, drizzle with warm queso, and garnish with desired toppings.