Roasted Sweet Potatoes

Name: Roasted Sweet Potatoes
Ingredients: 3 sweet potatoes; 1 tbsp olive oil; 1/2 tsp chili powder; 1/4 tsp paprika; 1/4 tsp cinnamon; 1/4 tsp garlic powder; 1/4 tsp onion powder; salt (pinch); pepper (pinch)