The combination of crispy potatoes and spicy tomato sauce makes this appetizer simply irresistible. If you prefer less heat, use one jalapeño pepper instead of two.
Preheat oven to 425°F. In large skillet, heat 4 tablespoons oil over medium-high heat. Add potatoes, and cook, stirring often, until browned, about 8 minutes. Transfer potatoes and any oil remaining in skillet to baking dish, and bake until crisp and tender, about 12 to 15 minutes.
In same skillet, heat remaining tablespoon oil. Add onion and garlic, and cook, stirring often, until onion is softened, about 5 minutes. Add remaining ingredients, and simmer, uncovered, 10 to 12 minutes. Transfer potatoes to serving bowl. Add tomato mixture, and toss to coat. Serve warm.