In a small saucepan, add water; bring to a boil. Add the oats; reduce heat to simmer. Cook for about 5 minutes. Stir in the nutritional yeast, hummus, salt, 1/4 teaspoon pepper, and cayenne pepper. Divide into two bowls.
While the oats are cooking, heat a little olive oil in a skillet over medium heat. Add chopped kale and stir; cook until slightly wilted, about 5-7 minutes. Add black beans; season with salt and pepper. Cook for 1 more minute. Top each bowl of oatmeal with half the mixture.
In a plate or shallow bowl, add soy sauce, hot sauce, olive oil, agave, liquid smoke, onion powder, garlic powder, cumin, and 1/4 teaspoon pepper; mix well. Add sliced tempeh in the marinade. Let it sit for 3-5 minutes.
In the same skillet over medium heat, warm a little oil. Add tempeh to the pan, cooking in two batches if necessary. Cook tempeh until slightly charred, about 3 minutes; flip and cook for another 2-3 minutes.
Top oatmeal with tempeh, 1/4 avocado each, and additional hummus (optional).