Combine all the ingredients in a small bowl. Leftovers can be stored in the refrigerator in a tightly sealed container for 1 week.
Prepare the batter:
Combine the flour, rice flour, egg, and water in mixing bowl. The consistency should be that of thin pancake batter
Add the leeks, red pepper, salt, and pepper and combine
Heat about 1 Tbsp oil in a large skillet over medium-high heat. With a ladle, spoon about a cup of the batter into the pan and spread it thin and wide into a large circle about 8 inches in diameter. Cook until the edges get slightly brown and the center starts becoming slightly translucent, 3 to 4 minutes. Flip the pancake and cook on the other side for 3 to 4 minutes. Place the cooked pancake on a cutting board
Repeat until all of the batter is used, stacking the pancakes on top of each other. Carefully cut the pancakes into wedges or other manageable pieces and serve immediately with seasoned soy sauce for dipping