1. Prepare the Dough:

• In a large mixing bowl, combine the masa harina, salt, and warm water. Mix until the dough is smooth and slightly sticky but firm enough to hold its shape.
• If the dough feels too dry, add a little more water, a tablespoon at a time. If it’s too wet, add more masa harina.
• Let the dough rest for about 10 minutes. This helps it become more pliable and easier to work with.

2. Make the Curtido:

• In a separate bowl, combine the shredded cabbage, onion, grated carrots, and minced garlic.
• In a small saucepan, bring vinegar, water, oregano, sugar, and a pinch of salt to a boil.
• Once boiling, pour the hot vinegar mixture over the cabbage mixture and stir to combine.
• Allow it to marinate for at least 15 minutes (you can also prepare this ahead of time and let it sit for several hours).

3. Prepare the Salsa Roja:

• In a small saucepan, heat the olive oil over medium heat.
• Add the diced tomatoes, onion, garlic, and jalapeño (if using). Cook for about 10 minutes, or until the tomatoes break down.
• Add oregano, salt, and pepper, then simmer for another 5-10 minutes, allowing the flavors to meld together.
• Use a blender or immersion blender to puree the salsa until smooth.

4. Prepare the Fillings:

• Cheese: Simply shred the mozzarella or quesillo.
• Beans: Heat the refried beans until they’re soft and warm, and season with salt if necessary.
• Ground Pork: If using ground pork, cook it with a bit of onion and garlic in a skillet until browned, then season with salt and pepper.
• Squash: If using squash, cook it until soft, mash, and season with a pinch of salt.

5. Form the Pupusas:

• Take a small ball of dough (about the size of a golf ball) and flatten it between your palms to form a small disc (about 4-5 inches in diameter).
• Add a spoonful of your chosen filling in the center (cheese, beans, pork, squash, or loroco).
• Carefully fold the edges of the dough around the filling to seal it inside, then gently press it back into a flat disc.
• Be gentle while pressing to avoid breaking the dough.

6. Cook the Pupusas:

• Heat a griddle or cast-iron pan over medium heat. Lightly oil the pan if needed.
• Cook each pupusa for about 3-5 minutes on each side, or until golden brown and crispy. Press gently with a spatula while cooking to ensure they cook evenly.
• Turn them carefully, making sure they don’t burst open.

7. Serve:

• Serve the pupusas hot with a side of curtido and a drizzle of salsa roja for dipping.
• Enjoy them as a main dish or a delicious snack!