Dice the sweet potato into 1/2-inch cubes and set aside—uniform sizing ensures even cooking. Finely chop the yellow onion and green bell pepper into 1/4-inch pieces, mince the garlic cloves, and set all vegetables aside separately. In a small bowl, combine the salt, black pepper, chili powder, cumin, paprika, smoked paprika, oregano, and red pepper flakes. Having everything prepped and measured before you start cooking will keep the process smooth and prevent burning of aromatics.
Heat 2 tablespoons of olive oil in a large skillet over medium-high heat until shimmering. Add the ground beef and cook without stirring for 2-3 minutes to develop a good crust, then break it up with a spoon and continue cooking until no pink remains and the beef is nicely browned, about 5-7 minutes total. Drain the excess grease from the pan, leaving just enough to coat the bottom—this fat carries flavor and helps sauté the vegetables.
Add the remaining 2 tablespoons of olive oil to the pan with the cooked beef. Add the diced onion and bell pepper, and sauté for 3-4 minutes until they begin to soften and release their aromatics. Push the vegetables to the side, add the minced garlic to the empty space, and let it cook for about 30 seconds until fragrant—this prevents the garlic from burning while allowing it to infuse the oil with its flavor.
Add the diced sweet potato cubes to the pan and stir to combine with the beef and aromatics. Sprinkle the spice blend from Step 1 over everything and stir well to coat all the ingredients evenly. The spices will toast slightly in the residual heat, deepening their flavors—I like how this releases their essential oils and makes the entire dish more aromatic.
Reduce heat to medium and cook the hash for 10-15 minutes, stirring occasionally, until the sweet potato cubes are fork-tender and slightly caramelized on the edges. The bottom of the pan may develop some flavorful browned bits—scrape these up as you stir, as they add depth to the dish. Taste and adjust seasonings if needed before serving.