"Hotteok is a street food in Korea. It's a flat bread filled with yumminess. Although my recipe may differ from the traditional ones, my family craves it all the time. You can also change the filling to whatever you like. If you have a sweet tooth, you may want to try this! And don't forget to smile when you finish eating hotteok."
Combine flour, yeast, and 2 teaspoons white sugar together in a bowl.
Stir milk and water together in a microwave-safe bowl and heat until lukewarm, about 20 seconds. Pour milk mixture into the flour mixture and mix with a fork until dough is evenly combined.
Turn dough onto a lightly floured surface and knead for 2 minutes. (Dough will be sticky.) Add salt to the dough and knead until dough is smooth, 2 minutes more. Shape dough into a ball, place on a floured surface, cover with a wet paper towel, and let rise for 10 minutes.
Mix brown sugar, 1/4 cup white sugar, walnuts, sesame seeds, and cinnamon together in a resealable plastic bag. Close bag and shake until filling is evenly combined.
Roll dough into a cylinder, cut into 10 pieces and form each into a ball. Roll each ball into a 5-inch circle using a rolling pin. Place dough into the palm of your hand and spoon 2 tablespoons filling into the middle of the dough. Wrap dough around filling, forming into a ball by taking 4 corners of dough, pinching together in the middle. Take another 4 corners and pinch together, sealing completely. Place balls, seam-side down, onto a floured surface.
Roll each ball into a 5-inch circle using a rolling pin, making sure filling stays in dough.
Place margarine in a skillet, spreading around with a paper towel; heat over medium heat. Place dough in the melted margarine and cook until golden brown, 5 to 10 minutes per side.