Heat half of the oil in a large skillet over medium-high heat. Once oil is shimmering, add the sweet potato noodles and season with garlic powder, chili powder, salt, and pepper. Toss and saute until cooked through, about 7 minutes.

Place cooked sweet potato noodles into a medium mixing bowl and let cool for 5 minutes in the refrigerator. Once cooled, add one egg and toss well to combine.

Heat the remaining oil in the same large skillet. Once oil is shimmering, add about ¼ cup of the sweet potato mixture, repeating until skillet is full (about 3-4 portions.) Flatten each portion with the back of a spatula and let cook until bottom is set. Flip and let cook 3 minutes, flattening again with the back of spatula, until cooked through and crispy. Repeat with remaining raw mixture, if needed.

Divide the sweet potato tostadas between four plates. Immediately coat the skillet with cooking spray and add in as many eggs as you can fit. Fry the eggs until egg whites are set.

Meanwhile, spread each sweet potato tostada with refried beans, a handful of spinach, and avocado. Once eggs are done, top each tostada with a fried egg and top with salsa and cilantro. Sprinkle with cheese, if using.