Medium heat is my preference for these. Gives them time to cook through before they brown too much. Make some curtido to go along with it, but it needs at least a day to ripen.
I have used these two recipes for both curtido and pupusas, but they are for HUGE batches and not well written. It assumes you can mix or buy your own masa dough. Make about 1/4 the listed amouts and it works out for my family. I really should write down what I actually do as it varies from these instructions.
CURTIDO (PICKLED CABBAGE)
1 medium cabbage, shredded
2 carrots, shredded
1 small red onion, sliced thin
4 cups cider vinegar
4 cups water
1 tablespoon dried oregano leaves, crushed
2 teaspoons crushed red chile flakes
1 red bell pepper or 4 ajies dulces (sweet red peppers), sliced thin
1 tablespoon salt
PORK AND POTATO FILLING
3 pounds pork butt, trimmed and cut
into small pieces
1 teaspoon salt
1 pound tomatoes (about 3 medium)
1/2 small white onion, sliced
1/2 teaspoon dried oregano leaves
1/4 teaspoon gound black pepper
3 whole cloves
1 large russet potato
4 pounds masa (freshly ground corn dough) 1 cup vegetable oil
1. Preparing the curtido: In a large bowl, combine the cabbage, carrots,
onion, vinegar, water, oregano, chile flakes, red bell pepper, and salt
until well mixed. Trasfer to a glass or plastic 1-gallon jar. Secure with
the lid and agitate to mix well. Let marinate at least 1 day. Makes 1
gallon. This mixture will keep up to 1 month in the refrigerator.
2. Preparing meat for filling: In a small pot, combine the pork with water
to cover by 2 inches and salt to season. Bring to a rapid simmer.
Partially cover and cook until the pork is tender and the water has almost
evaporated, about 40 minutes. Uncover; reduce the heat to very low and let
the pork fry in its own fat until golden. Remove from the heat.
3. Simmering the filling: Put the tomatoes, onion, oregano, black pepper,
and cloves in a blender container. Puree until smooth. Pour the blender
contents into the saucepan with the pork. Place over medium heat, stirring
the puree with a wooden spoon to loosen bits of browned pork on the bottom
of the pot. Remove from the heat and, using 2 forks, shred the meat. Bring
the mixture to a boil again. Lower the heat and cook uncover over medium
heat for 10 minutes, or until thickened.
4. Finishing the filling: Place the potato in a small pot with water to
cover. Bring to a boil and cook until tender, 20 to 30 minutes. Remove
from the heat, drain, and peel. Mash the potato or press it through a
sieve. In a bowl, combine the pork mixture with 1/2 to 3/4 cup of the
mashed potato; mix thoroughly. Makes about 4 cups filling.
5. Forming and cooking pupusas: Mix the masa with the oil until very soft.
Form into 25 small balls and cover with a damp cloth. Pat each ball with
the palms of your hand until flattened. Place a generous tablespoon of
meat mixture in the center of each round. Carefully enclose the filling by
pressing the edges of the masa up over the filling. Press the edges of
masa together to seal the ball. Lightly pat the masa ball (with enclosed
filling) until flattened to 3/8-inch thickness. Place the pupusas on a
heated greased grilled; cook until speckled brown. Turn once and continue
coocking until speckled and puffed. Remove; top with curtido and serve.
SERVING SUGGESTION: El Salvador's most popular snack is similar to a thick
corn tortilla stuffed with cheese, or in this version, pork and potatoes.
Be sure to top the hot pupusas with curtido, a colorful pickled vegetable
mixture of cabbage, carrots, and onion. For a party hors d'oeuvres,
prepare miniature 2-1/4 inch pupusas up to 1 week ahead and freeze. Heat
thawed pupusas in a 350 degrees Faranheit for 20 minutes, or until heated
through. Serve hot.