Place sweet potatoes in a medium pot of lightly salted water, just enough to cover sweet potatoes. Bring sweet potatoes to a boil over medium-high heat, then reduce heat to medium and let potatoes simmer until just barely tender, about 5 minutes. (a paring knife should go through a cube with just a bit of resistance) Drain sweet potatoes and pat completely dry with paper towels.
Preheat oven to 400F. In a 9-in cast iron skillet or a large regular skillet, heat 1 tablespoon oil over medium-high heat until shimmery. Add pepper and onion and saute 2-3 minutes until vegetables are tender.
Add spinach, chickpeas, garlic, and paprika and saute an additional 2-3 minutes until spinach is wilted. Season with salt and pepper to taste and transfer mixture to a bowl.
Heat remaining 2 tablespoons oil in same skillet over medium-high heat until shimmery. Add pre-cooked and dried sweet potatoes in a single layer in pan. Let sweet potatoes cook without stirring 2-3 minutes until crispy, then use spatula to flip to opposite side and cook an additional 2-3 minutes until crispy. Season sweet potatoes with salt and pepper to taste.
Lower heat to medium and toss bell pepper mixture into pan fried sweet potatoes until combined. Form 4 "nests" in hash and carefully crack an egg into each nest. Transfer skillet to oven and let eggs bake at 400F 7-9 minutes until whites of egg are set.
Season eggs with salt and pepper to taste and top skillet with parsley and feta if desired. Serve hash immediately and enjoy!