Open the can of black beans and pour the entire contents into a measuring cup. If there is more than 1/2 cup liquid, measure and set aside 1/2 cup of the liquid; if there is less than 1/2 cup, reserve all the liquid. Transfer the beans to a bowl or leave them in the can until ready to add to the pan.
Warm the tortillas: heat them in a dry skillet over low–medium heat for about 20–30 seconds per side, or wrap in a damp paper towel and microwave for 20–30 seconds. Keep warm until assembly.
Heat 1 tablespoon olive oil in a large skillet over medium heat until the oil shimmers.
Add 1/2 teaspoon cumin, 1/2 teaspoon dried oregano, and 1/2 teaspoon chipotle chili powder to the hot oil. Stir and cook about 30–60 seconds, until the spices are fragrant.
Add the black beans, the reserved liquid (up to the 1/2 cup you set aside), 1 tablespoon finely chopped pickled jalapeños, 1 tablespoon pickled jalapeño juice, and 1/2 teaspoon salt to the skillet. Stir to combine.
Lightly mash the beans in the skillet using a potato masher or the back of a wooden spoon, leaving some whole beans for texture.
Reduce heat to low and simmer, stirring occasionally, about 5 minutes, until the mixture has thickened to your desired consistency. If you reserved more liquid than you added, add a little of that remaining liquid 1 tablespoon at a time while simmering until you reach the preferred texture.
Spoon the refried black bean mixture into the warmed tortillas and top with sour cream, shredded cheese, fresh cilantro, shredded romaine or iceberg lettuce, hot sauce or salsa, and shaved red onion or thinly sliced radish. Add extra pickled jalapeños on top if desired.