Heat 2 tablespoons of olive oil in a skillet over medium heat. Stir in the onion; cook and stir until the onion has softened and turned translucent, about 5 minutes. Reduce heat to medium-low, and continue cooking and stirring until the onion is very tender and dark brown, 15 to 20 minutes more.
Layer half the potatoes on the bottom of a slow cooker.
Add the cooked onions and rice; top with the remaining potatoes and beets.
Nestle the eggs into the mixture: they should be almost completely submerged when you add the water.
Mix the garlic powder and seasoned salt into 1 cup of water.
Pour over the cholent. Season with salt and pepper.
Drizzle with 1/4 cup of olive oil.
Add water to cover. Too much water will make your cholent mushy; not enough may cause it to burn.
Cover with the lid and set your slow cooker on low; cook overnight.