Preheat your grill or a skillet over medium-high heat.
In a small bowl, mix together the olive oil, garlic powder, onion powder, smoked paprika, salt, and pepper. Rub this mixture all over the skirt steak.
Grill the skirt steak for about 4-5 minutes on each side, or until it reaches your desired level of doneness. Remove from heat and let it rest for 5 minutes before slicing against the grain.
While the steak is resting, prepare the rice bowls. In each bowl, add a base of cooked white rice.
Top the rice with black beans, corn, diced tomatoes, and sliced avocado.
Slice the rested skirt steak and arrange it on top of the bowls.
Squeeze fresh lime juice over each bowl and garnish with cilantro.