Slightly crunchy, tangy, creamy, and hearty, pambazos are a popular Mexican street-food that will surely up your sandwich game. The secret’s in the guajillo sauce.
Toast the peppers. Place a skillet over high heat. Add the peppers and toast until they puff up, turning every 15 seconds or so. Turn the heat off.
Hydrate the peppers. Add enough boiling water to the skillet to cover the peppers. Let the peppers soak for 30 minutes or until soft.
Saute the aromatics. Heat a skillet over medium-high heat and add the olive oil. Add the diced onion and saute for 2 minutes or until translucent. Add the garlic and saute for 20 seconds or until fragrant.
Blend. Drain the peppers, reserving ½ cup of the cooking liquid, and remove the stems. Transfer the peppers to a blender along with the sauteed onions and garlic, and add salt and pepper. Blend until smooth, then set aside. If the mixture isn't smooth, add some of the cooking liquid to the blender and process until smooth.
For the potato-chorizo filling (make the filling while the peppers are hydrating)
Boil the potatoes. Bring a pot of water to boil over high heat and add ½ teaspoon of salt along with the diced potatoes. Reduce the heat to medium-low and boil the potatoes for 5 minutes or until fork tender.
Cook the chorizo. Place a large, heavy-bottomed pan over medium-high heat and add the canola oil. Add the chorizo, season with oregano, and cook until nicely caramelized and cooked through, crumbling it with a wooden spoon as you go.
Put it all together. Drain the potatoes and add them to the pan with the chorizo. Season with smoked paprika and saute for a few minutes until the potatoes get a little crispy. Taste and season with additional salt if needed.
To assemble.
Toast the buns. Set the oven to broil and brush the cut sides of each bun with olive oil. Place the buns, cut side up, on a baking sheet and broil for 1 minute or until golden brown.
Assemble. Brush both cut sides of each bun liberally with the guajillo sauce. Divide the chorizo mixture evenly between the buns and top with pickled red onion, romaine lettuce, cotija cheese, crema, and salsa. Close the pambazos with the other half of the bread and serve.