Preheat your oven to 375°F (190°C).
Peel the sweet potato and dice it into small, uniform half-inch cubes to ensure even cooking.
Remove the tough stems from the kale and roughly chop the leaves into bite-sized pieces.
Heat the olive oil in an 8-inch oven-safe non-stick skillet over medium heat.
Add the diced sweet potatoes to the skillet and sauté for 8-10 minutes, stirring occasionally, until they are tender and lightly caramelized.
Add the chopped kale to the skillet and cook for 2 minutes until it has wilted and turned a bright green.
In a medium bowl, whisk together the whole eggs, egg whites, sea salt, black pepper, and garlic powder until well combined and slightly frothy.
Pour the egg mixture over the vegetables in the skillet, ensuring the sweet potatoes and kale are evenly distributed.
Cook on the stovetop for 3 minutes without stirring, allowing the bottom and edges to begin to set.
Transfer the skillet to the preheated oven and bake for 10-12 minutes, or until the center is firm and the top is slightly golden.
Remove from the oven and let the frittata rest for 5 minutes before slicing into wedges and serving.