Warm the oil in a skillet over medium heat. When the oil is hot, add the sliced peppers and onion and stir. Continue to cook, stirring only occasionally, until the vegetables are slightly browned and softened a bit, about 5-6 minutes.
Add the cumin, paprika, black pepper, and salt to taste, and stir well to combine. Reduce the heat to medium-low and continue cooking until the onion is soft, about 2-4 minutes more.
For the vegan kimchi quesadillas:
Drain any excess liquid from the kimchi and finely chop it.
Lay a tortilla flat and spread about 1/2 cup of refried beans onto it, leaving a little bit of space around the edges. Spread about half of the chopped kimchi onto the refried beans, and finally, top with about half of the cooked vegetables. Fold the tortilla in half and press down on it gently to seal. Repeat with the remaining tortilla and ingredients.
Wipe out the skillet and return it to medium-high heat. Add the vegetable oil. Once hot, add one of the folded quesadillas to the skillet. Cook for 2-3 minutes on each side, or until golden brown. Repeat with the second quesadilla.
Serve hot, garnished with chopped scallions and sesame seeds if desired, and condiment of choice (I recommend something mayo-based).
Notes
KIMCHI: Traditional kimchi isn't vegan, but many brands of kimchi sold in grocery stores omit the fish sauce to cut costs. Just check the label to be sure.CHEESE: You'll notice these kimchi quesadillas are cheese-less, because I don't care for vegan cheese. If you want to use vegan or regular cheese according to your dietary and taste preferences, sprinkle it over the vegetables before folding up the quesadillas.TORTILLAS: Use some kind of gluten-free tortilla if needed. I almost always use whole wheat flour tortillas, personally, although the pictured quesadilla is made with a white flour tortilla.