Bring a medium saucepan of water to a boil over medium-high heat. Add the tomatoes and cook for 5 minutes. Remove the tomatoes and set aside to cool slightly.
In a heavy medium skillet, heat the vegetable oil over medium heat. Add the fideo or pasta and cook until golden brown, about 6 minutes.
Place the cooked tomatoes, onions, and 1/2 teaspoon salt in a blender. Blend until smooth. Add the tomato mixture to the skillet and cook the fideo or pasta on low heat, without stirring, until tender, about 12 minutes. Season with salt and pepper, to taste.
Fill the tortillas with the fideo filling. Drizzle the tacos with crema and sprinkle with cheese.