Preheat your oven to 400°F.
Peel the sweet potato and cut it into small, even bite-sized cubes.
Toss the sweet potato cubes on a baking sheet with half of the olive oil, salt, and half of the dried oregano.
Roast for 20-25 minutes until the potatoes are tender and show golden caramelized edges.
While the potatoes roast, season the tilapia fillets with minced garlic, lime juice, the remaining oregano, and a pinch of salt.
Heat the remaining olive oil in a large non-stick skillet over medium-high heat.
Add the sliced peppers and onions to the skillet and sauté for 3-4 minutes until they are softened and slightly charred.
Push the vegetables to the outer edges of the pan and place the tilapia fillets in the center.
Sear the fish for 3-4 minutes per side until it is opaque, golden, and flakes easily with a fork.
Plate the tilapia alongside the roasted sweet potatoes and sautéed vegetables, finishing with an extra squeeze of fresh lime juice.