Preheat oven to 350 degrees.
Grease a 9×13 casserole dish.
In large pan over medium- high heat, cook the bacon, adding diced onion after 5 minutes.
Continue to cook until bacon is done and onion is caramelized.
Put onions and bacon aside on plate with paper towel (to soak up some grease).
Return pan to heat. In multiple batches, lay slices of sweet potato into pan to brown. Flip and brown other side.
Cover the base of casserole dish with sweet potato slices and season with salt and pepper.
Using half of mixture, add layer of bacon and onion mixture.
Beat eggs and water with fork or whisk until well combined.
Gently pour the mixture over over the ingredients in baking dish.
Bake 50-60 minutes until the top is golden brown and egg mixture has set.
Remove from oven then set aside for 5-10 minutes before cutting and serving.
Serve and enjoy!