Make the stock: Peel and devein the 1 pound fresh shrimp and save the shells. Cover and refrigerate the shrimp until ready to use.

In a large stock pot or Dutch oven, heat 1/4 cup of the avocado oil over medium heat. Add the shrimp shells along with the 7 ounces dried shrimp, 1/2 of the onion, and 2 cloves garlic. Fry for about 3 minutes, or until garlic is golden.

Add 12 cups of cold water, bring to a boil, then reduce the heat to a simmer and cook gently for 30 minutes.

Let cool slightly. Transfer to a blender and blend to a puree (see note for blending hot liquids). Strain into a large bowl or container and discard solids. Set aside while you make the chile base. Clean the blender and the soup pot, you will need them again.

Fill a large saucepan with water and place over high heat until it comes to a simmer, this will be the hot water you will soak the chiles in.

Heat a large dry frying pan, comal or cast iron skillet over medium heat. Lay the 10 guajillo chiles in the pan (maybe doing this in batches depending on the size of your pan) you don't want them too crowded. Toast the guajillo chiles for 30 seconds to a minute per side until fragrant but not burnt. Transfer them to the saucepan on simmering water once toasted.

Now toast the 2 arbol chiles just like you did with the guajillos and place them in the simmering water. Push all the chiles down so they are completely submerged. Remove the pan from the heat and let soak until really soft, about 30 minutes.

While the chiles are soaking, char the other half of the onion, the 4 roma tomatoes, and remaining 4 cloves of garlic on the comal or pan you just used to toast the chiles. Again, do this in batches to not overcrowd the pan.

Remove the vegetables to a blender once charred and blackened on all sides. Once the chiles are soft and tender, drain and add them to the blender as well, along with the 1 tablespoon dried oregano and a teaspoon of kosher salt. Blend until smooth.

Heat remaining 1/4 cup of avocado oil over medium heat in the large stock pot or Dutch oven. Once hot, carefully add the chile sauce, stir as soon as you can to prevent too much sputtering. Let cook, stirring constantly, until it is fragrant and the color has darkened, about 5 minutes.

Add the strained shrimp broth and bring to a simmer. Add the potatoes and carrots and simmer gently until they are tender, about 20-30 minutes.

Add the zucchini and the epazote (or cilantro). Let it cook for 5 minutes. Finally, drop in the fresh shrimp. They only need 3–5 minutes to turn pink and opaque. Don't overcook them! Taste and season with more salt until it tastes vibrant and rich with bold shrimp flavor.

Serve: Ladle into big bowls. Top with plenty of lime juice, chopped onion, salsa macha, and fresh cilantro.