Optional Step: Heat a large pot over medium-high heat. Cut the tops off the tomatoes and add them to the pot, along with the onion. Let them cook, stirring occasionally, for 4-5 minutes to get some char. Use this pot for the following steps.
4 Large Roma Tomatoes, 1/2 Medium White or Yellow Onions
Add the tomatoes, onion, garlic and a heavy pinch of salt to a blender. Blend until smooth.
2 Cloves Garlic, Salt to Taste
Heat the oil in a large pot over medium-high heat. Add in the fideo/vermicelli. Cook, stirring often, for 5 minutes. the pasta should toast, turning darker and taking on a nutty aroma.
16 Oz. Fideo or Vermicelli, 6 Tbsp Vegetable Oil
Stir the tomato puree in with the pasta. Add the broth, cumin and (optional) oregano, and bring to a boil.
16 C Chicken Broth, 1/2 tsp Ground Cumin, 1/2 tbp Oregano
Cover the pot, reduce the heat to a simmer, and cook for 10 minutes.
Taste for salt one last time before serving. Serve with a side of lime wedges and sliced avocado (optional).
2 Large Avocados, 4 Limes