These are so good with drained and chopped kimchi in them, so good with chicken bulgogi, and so good with grilled onions in them. They are just so good in general. This is the most basic recipe because there is so much flavor from the bulgogi and the cheese, but feel free to experiment- with fillings, toppings, and everything else.

Preparation

1. Grill or stir fry bulgogi according to this recipe.
2. Place tortilla on a flat surface and top with some shredded cheese and bulgogi.
3. Top with more shredded cheese. 
4. Place another tortilla on top.
5. Cook gently in a cast iron skillet until cheese is melted through.
6. Cut into triangles. 
7. Serve with sour cream, salsa, guacamole on the side.

Some Quesadilla History:

"According to Mexican food history, many of the traditional Mexican foods have roots in other cultures as well as the Mexican culture.

For instance, quesadillas, a mainstay in Mexico and considered to be authentic Mexican food actually not only have roots in Mexican traditions, but in Spanish as well. The corn tortilla, thought to be quintessential Mexican, is actually native American.

The cheese, pork, beef, and lettuce that grace so many of our favorite Mexican dishes, including the quesadilla, are Spanish. The hot sauce that is made from chili pepper, though, is indigenous to Mexico. However, it is a little known Mexican food history fact that many of the spices thought to be Mexican are actually Spanish in origin. Black pepper, cinnamon, coriander and oregano are several spices that are often used in Mexican cooking but are not native to the country.

The French are yet another chapter in Mexican food history. Under a brief French occupation in the 1860's, Mexico was introduced to other new foods and cooking methods. This resulted in popular dishes like stuffed chilies in a walnut sauce, known as chiles en nogado. These dishes, French inspired with a strong Mexican flair, have made their way through the various cultures to meld together and create dishes that the world can enjoy."

Source: Food Editorials

Some Korean-Mexican Food 'History':

Korean–Mexican fusion is a type of fusion cuisine in the United States that combines traditional elements of American-style Mexican food and Korean food. Typically, Mexican wrappings like tortillas and taco shells are filled with traditional Korean ingredients like kimchi. Typical dishes include Korean tacos and bulgogi burritos. Korean–Mexican fusion is a growing food trend that has steadily gained in popularity since 2009.

Restaurants serving Korean tacos have existed in the United States at least since 1996. However, Korean–Mexican fusion first gained widespread popularity in 2009, after the first food truck serving Korean tacos, Kogi Korean BBQ, opened in Los Angeles in late 2008. In the following years, food trucks serving Korean–Mexican fusion opened in several cities across the U.S., including Austin, Chicago, Portland, Seattle and Washington.

Source: Wikipedia