Prepare curtido the day before you plan to make the pupusas.
Shred the cabbage and cut the carrots into match sticks. Slice the jalapeno.
Salsa
Blend tomatoes, onion, garlic, and chilies until smooth.
Heat oil in pot or a pan. Add the blended vegetables and cook for 5-10 minutes. Add salt to taste.
Let cool. Can be prepared the day before as well.
Refried beans
Blend beans, onion, and garlic with salt. Add water if needed but sparingly.
Heat oil in a pan. Cook the bean puré for 10-20 minutes or longer on medium heat. Stir to prevent burning. It should thicken and adopt a texture similar to Play-doh. It will thicken more as it cools.
Let the beans cool. The beans can be prepared the day before.
Pupusa dough
Prepare the pupusa dough by adding the masa harina and salt to a bowl.
Add water, a bit at a time to the masa and work into the flour.
Keep adding water to the dough until it adopts a stiff, somewhat sticky texture. To test, you should be able to form the dough into balls that hold their shape and don't all apart. The dough should not stick to your hands.
Make the pupusas
Take a bit of dough and form it into a ball.
Create an indentation in the ball using your fingers.
Add some refried beans and some vegan cheese to the hole.
Close the pupusa by working the sides upward into a bowl shape and then closing the bowl. Pinch of any surplus dough.
Work the filled pupusa back into a ball shape and then flatten it. You can wet your hands with oil or water to make sure the dough doesn't crack.
Fry the pupusa in a lightly oiled pan. A few minutes per side to create a slightly browned surface.
Serve the pupusas with curtido and a red salsa of your choice.