For Polenta: Bring water to a boil in a saucepan over medium-high heat. Add salt. Once water is at a boil, add cornmeal in a slow stream, whisking constantly.
Continue to whisk cornmeal until mixture starts to thicken and doesn't immediately settle to bottom. Turn heat to low, place a lid on saucepan and allow to simmer for 30 minutes. Stir about every 10 minutes or so, being sure to scrape sides down. Polenta is done when it has reached a porridge-like consistency.
For Beans: While polenta is cooking, heat olive oil in a small saucepan over medium heat. Once oil is warmed add black beans, spices, and lime juice. Stir to combine, reduce heat, and cook until warm.
For Assembly: Fry up your eggs as you like. Divide polenta amongst bowls. Do the same with black beans, avocado slices, and feta. Top with eggs and add salsa or hot sauce as you please. Sprinkle with cilantro and season with salt and pepper as desired.